clinical reports
PAUL R. MANSKE, MD, and PEGGY GLEESON, BS
A rehabilitation program which has been used successfully in improving the postoperative range of motion of patients undergoing total knee arthroplasty is outlined. The specific objectives are strong quadriceps setting, straight leg raising, flexion of the knee to at least 90 degrees, and extension of the knee to 0 degrees. The program emphasizes the importance of early institution of exer cises and early ambulation.
The development of the first hinge-type total knee replacement prosthesis by Waldius in 1951 and the first resurfacing type of total knee replacement prosthesis by Gunston in 1968 proved to be major contributions to re constructive surgery of the arthritic knee. 1,2 Since then, over 300 different models have been developed based on the original designs of Waldius and Gunston. 3 Although the primary indication for total knee surgery is the presence of pain, patients may also have varus or valgus deformities and limited motion, both in flexion and extension. Fortunately, about 85 percent to 95 percent of patients have significant relief of pain following total knee replacement surgery regardless of the model used. 4-7 Most knees are stable post operatively, indicating adequate correction of the varus or valgus deformities. Little success has been reported in increasing range of motion postoperatively, however. Gunston reported no change in range of mo tion. 8 Ilstrup reported an average improve ment of 7.3 degrees of motion in patients with rheumatoid arthritis and no change in patients Dr. Manske is Assistant Professor of Orthopedic Surgery, Divi sion of Orthopedic Surgery, Dept of Surgery, Washington Univer sity School of Medicine, 4960 Audubon Ave, St. Louis, MO 63110. Ms. Gleeson is Staff Physical Therapist, Irene Walter Johnson Institute of Rehabilitation, Washington University School of Medi cine, 509 S Euclid Ave, St. Louis, MO 63110.
Volume 57 / Number 8, August 1977
with degenerative arthritis following polycen tric total knee arthroplasty. 4 The Mayo Clinic reported a 2 degree loss of motion following geometric total knee arthroplasty. 5 The duo condylar knee replacement averaged 1 degree improvement in the arc of motion. 6 Marmour reported a 1 degree loss of motion using the modular knee replacement. 7 A review of 56 consecutive polycentric total knee arthroplasties reported by the senior au thor indicated a statistically significant im provement in postoperative range of motion. 9 Patients with rheumatoid arthritis had an aver age increase in the motion arc of 18.5 degrees, those with degenerative arthritis an average increase of 8.7 degrees. The combined results of all patients in the series indicate an average increase of 13.7 degrees. The improvement was noted both in flexion and in extension; 96 percent of the operated knees had more than 90 degrees of flexion and 63 percent had greater than 110 degrees of flexion postopera tively. Only 2 patients (3.6%) lacked more than 15 degrees of extension. Improved motion is related to the design of the prosthesis and to careful surgical tech nique. We believe, however, that the vigorous postoperative exercise program which we use is of utmost importance in obtaining these re sults. This article outlines our rehabilitation program following total knee replacement sur915
Downloaded from https://academic.oup.com/ptj/article-abstract/57/8/915/4558978 by University of Texas at Dallas user on 03 February 2019
Rehabilitation Program Following Polycentric Total Knee Arthroplasty
gery. References about such programs are lim ited. 10-12 REHABILITATION PROGRAM
916
Downloaded from https://academic.oup.com/ptj/article-abstract/57/8/915/4558978 by University of Texas at Dallas user on 03 February 2019
The rehabilitation program begins in the preoperative period. In order to allay the pa tient's apprehension, the operative procedure and the postoperative exercise program are explained to him as simply and clearly as possi ble by the surgeon and the physical therapist. The patient is specifically instructed in quadri ceps setting and straight leg raising exercises. In the postoperative period, the patient is seen by the physical therapist twice daily and encouraged by the nursing staff to exercise throughout the day. The importance of each exercise is explained to the patient with the encouragement that best results are obtained with independent hourly exercising. The entire exercise program takes place in the familiar environment of the patient's room and on the hospital ward. The appropriate time for the administration of pain medication may be de termined by the physical therapist, the nurse, or the patient to ensure maximum voluntary effort during exercise sessions. A long leg cast is applied in the operating room to prevent the development of early knee flexion contracture. Forty-eight hours later, the cast is bivalved and the posterior half of the cast serves as a splint which is worn only at night to maintain complete knee extension. After the cast has been removed, three distinct exercises are emphasized: 1) quadriceps setting and straight leg raising, 2) flexion of the knee to at least 90 degrees, and 3) active extension of the knee to 0 degrees. Quadriceps Setting and Straight Leg Raising. The most important aspect of the initial exer cise program is restoration of quadriceps func tion. Straight leg raising is encouraged in the immediate postoperative period while the pa tient is still in the recovery room. This exercise is stressed during the first 48 hours while the knee is immobilized in a cast. Straight leg rais ing is frequently easier to accomplish while in the cast than after the cast has been removed, because the cast is holding the knee in exten sion and is in effect substituting for the quadri ceps muscle. If the patient is unable to actively raise his leg, the therapist passively lifts it and asks the patient to hold that position. If the patient is still unable to initiate knee extension, he is
placed on his unoperated side, abducting and flexing the hip while keeping the operated knee extended. He then rolls back to the su pine position and attempts to perform hip flex ion and knee extension. Flexion. Active and active-assisted knee flexion is encouraged from the time the cast is removed. The patient begins by simply flexing and extending the hip in the supine position and allowing his heel to slide along the surface of the bed. An exercise sling is fashioned and attached to the overhead bar on the bed. The sling, consisting of felt and stockinette, is placed under the patient's thigh proximal to the knee. A rope is attached to it and passed through a pulley on the overhead bar. A small sandbag is attached to the opposite end of the rope. By pulling on the sandbag, the patient passively raises the thigh and assists the knee in flexion. For patients with arthritic deformities of the hands and wrists, another felt sling may be attached in place of the sandbag. The pa tient slips his forearms through this second sling and pulls. Knee flexion exercises are performed with the patient sitting in a chair. With the foot planted firmly on the floor, the patient gently slides his buttocks forward toward the edge of the chair, flexing his knee as much as possible. After holding this position for a few seconds, he slides backwards in the chair. This exercise can also be performed in a wheelchair. After planting his foot firmly, he rolls the wheelchair forward to obtain maximum knee flexion and then rolls the chair backward. Ninety degrees of flexion is usually attained within 12 days after surgery. When this range is not obtained, passive manipulation into flex ion under general anesthesia by the surgeon may be necessary. Only 3.6 percent of the knee arthroplasties in our series required such manipulation. Extension. In his enthusiasm to achieve max imum knee flexion and to regain his quadriceps muscle strength, the patient tends to overlook the importance of knee extension to 0 degrees. In order to prevent flexion contractures, the foot of the bed is always flat and at no time is a pillow allowed underneath the operated knee. If the patient is unable to passively extend his knee to 0 degrees, a small pillow or rolled towel is placed under the patient's heel when he is supine. The patient is instructed to flatten the popliteal fossa against the bed. When the patient is sitting in a chair, a stool is placed PHYSICAL THERAPY
Volume 57 / Number 8, August 1977
patient has a very strong quadriceps muscle we do not encourage use of more than eight pounds of weight. DISCUSSION
Daily activites of arthritic patients are fre quently limited by pain, varus or valgus de formity, or inadequate range of motion. The relief of pain and the correction of the deform ity are dependent upon the design of the pros thesis and the operative technique of the sur geon; the improvement of knee motion is de pendent upon the rehabilitation program. Al though we are not trying to minimize the im portance of a stable and pain-free total knee arthroplasty, we believe that the significance of increased range of motion has been overlooked by surgeons and therapists. The importance of knee flexion to 90 de grees is well accepted and some authors believe that 110 degrees of flexion is necessary. 13 We believe that this amount of flexion can only be attained with a vigorous exercise program which includes quadriceps setting in the imme diate postoperative period and range of motion exercises beginning the second rather than the seventh postoperative day. 11,12 The impor tance of knee extension to less than 15 degrees has been documented. 14 Patients, however, are frequently so concerned with bending the knee and regaining strength that they tend to forget the importance of complete knee extension to 0 degrees. We believe that the patient benefits physio logically and psychologically from rapid reha bilitation. Consequently, we emphasize early ambulation with external support and weight bearing as tolerated. We have not experienced difficulties with wound management which could be attributed to early motion or early ambulation. Our rehabilitation program following total knee arthroplasty has been successful in terms of patient satisfaction, as well as improvement in knee stability, range of motion, and relief of pain. We consider the rehabilitation program to be an essential part of total knee arthro plasty and advise that it be pursued vigorously. REFERENCES 1. Waldius B: Arthroplasty of the knee using an acrylic pros thesis. Acta Orthop Scand 23:121, 1953 2. Gunston FH: Polycentric knee arthroplasty: Prosthetic simula tion of normal knee movement. J Bone Joint Surg 53 [Br]:272277, 1971
917
Downloaded from https://academic.oup.com/ptj/article-abstract/57/8/915/4558978 by University of Texas at Dallas user on 03 February 2019
under his foot and similar exercises are carried out. The patient is also instructed to passively extend the knee by manually exerting down ward pressure over the patella. Ambulation. When the patient is independ ently able to straight leg raise and has at least 60 degrees of knee flexion, ambulation with a walker is instituted. The patient is allowed to bear full weight on the operated extremity as tolerated. Patients usually experience very lit tle of the severe arthritic pain which they had preoperatively. They may complain of inci sional pain which is more tolerable than the deep pain. A normal gait is encouraged, in cluding equal stride length, full knee extension in the stance phase, and knee flexion during the swing-through phase. Most patients are in structed in stair-climbing techniques, especially if they have stairs at home. Before discharge, many of our patients have progressed to ambu lating with a standard cane, although patients are not necessarily encouraged to discontinue use of the walker. Posthospitalization. Patients are hospitalized an average of 3 weeks. At the time of dis charge, the exercise program is reviewed and the patient is instructed to perform each exer cise at home on a daily basis. Unless problems develop, he is not seen as an outpatient by the physical therapist until his regularly scheduled office visit 6 weeks after discharge. He is en couraged, however, to call the surgeon or the therapist if any difficulties or questions arise. The patient is seen in a follow-up clinic by the surgeon and the physical therapist at 6 weeks, 3 months, and 9 months, and at yearly inter vals thereafter.. At 6 weeks, many patients have discontin ued using the external support. The patient is questioned about the presence of pain, the use of external support, and difficulties in daily activities such as ambulating, stair climbing, or rising from a sitting position. The patient's gait is evaluated and examination of the stability and range of motion of the knee is made. By 3 months, the patient has usually pro gressed satisfactorily and is allowed to begin light quadriceps resistance exercises. He is in structed to sit on a table or counter and extend the knee with weights suspended from the an kle. Starting with one pound and gradually increasing the weight to a maximum of eight pounds, the patient extends and holds his knee in extension for 10 seconds 20 times both in the morning and in the evening. Unless the
3. Ewold FC: Metal to plastic total knee replacement. Orthop Clinic North Am 6:811-821, 1975 4. Ilstrup OM, Combs JJ, Bryan RS, et al: A statistical evalua tion of polycentric total knee arthroplasties. Clin Orthop 120:18-26, 1976
6. Ranawat CS, Insall J, Shim J: Duo-condylar knee arthro plasty. Clin Orthop 120:76-82, 1976 7. Marmour L: The modular (Marmour) knee. Clin Orthop 120:86-94, 1976 8. Gunston FH: Complication of polycentric knee arthroplasty. Clin Orthop 120:11-17, 1976
Forest Town Boot JAMES J. CRAIG, MB, B Ch, Dip Surg, and ANNA MATHIAS, BSc
The most common deformity of the feet in children with cerebral palsy is that of equinus, caused by an increase in muscle tone as a result of an exaggerated positive supporting reaction. Associated with the equinus may be a varus or a valgus deformity, and the deformity may be present in either a nonweightbearing or weightbearing position. The purpose of the Forest Town Boot is to enable a child with an equinus deformity of the foot because of an overactive positive support ing reaction to stand and walk with a planti grade foot (Figs. 1 and 2). The effect of the boot is to prevent shortening of the tendo Achilles and the long flexor muscles of the toes and to allow lengthening of the triceps surae while preventing lengthening of the dorsiflexor muscles of the foot. The most important thera peutic effect of the boot is the continuous stretch on the triceps surae muscle group (par ticularly the soleus muscle) and the long toe flexors, producing a lengthening of these two muscle groups. The static stretch of the soleus muscles and calcaneal weight bearing may be responsible for the reflex facilitation of the Dr. Craig is Principal Orthopaedic Surgeon, Orthopaedic De partment, University of the Witwatersrand, Medical School, and Johannesburg Hospital, South Africa. Mrs. Mathias is Chief Physiotherapist, Johannesburg Hospital, Private Bag X39, Johannesburg 2000, South Africa. This article was adapted from a paper presented by Dr. Craig at the Annual Meeting of the American Academy of Cerebral Palsy in New Orleans in 1975.
918
Downloaded from https://academic.oup.com/ptj/article-abstract/57/8/915/4558978 by University of Texas at Dallas user on 03 February 2019
5. Skolnick MD, Coventry MB, Ilstrup OM: Geometric total knee arthroplasty. J Bone Joint Surg 58 [Am]:749-753, 1976
9. Manske PR, DeBender JJ: Polycentric total knee arthroplasty. South Med J, to be published 10. Convery RF, Beber CA: Total knee arthroplasty, indications, evaluation, and postoperative management. Clin Orthop 94:42-49, 1973 11. Waters EA: Physical therapy management of patients with total knee replacement. Phys Ther 54:936-942, 1974 12. Paradis D, Hamlin C: Geometric and polycentric knee pros thesis. Phys Ther 53:762-768, 1973 13. Laubenthal KN, Smidt GL, Kettlekamp DB: A quantitative analysis of knee motion during activities of daily living. Phys Ther 52:34-42, 1972 14. Perry J, Antonelli D, Ford A: Analysis of knee joint forces during flexed knee stance. J Bone Joint Surg 57 [Am]:961967, 1975
dorsiflexors of the foot. 1 In our experience, the Forest Town Boot, used postoperatively, helps to reduce the recurrence rate of deformity. 2-4 CASTING AND MANUFACTURE OF THE FOREST TOWN BOOT
1. For casting, the physical therapist holds the child on her lap, facing the orthotist. 2. Stockinette is applied first, extending to just below the knee, with an excess of ap proximately 20 cm at the toes. 3. The therapist keeps the patient's knee in 90 degrees of flexion to prevent a sudden ex tension of the knee and foot. The foot is held in 10 degrees of dorsiflexion and slight varus. Proximal pressure applied with the excess stockinette holds the toes in a posi tion of maximal dorsiflexion and the foot, ankle, and knee positions are maintained during the casting procedure. The orthotist, while applying and molding the plaster bandages must ensure that the ankle and the foot positions are maintained and that the foot is not allowed to go into valgus (Fig. 3). 4. After the positive model has been made from the removed cast, the bony promi nences of the ankle must be well built up and the toes of the mold extended by 1.25 cm and given a round aspect. (The reason for extending the length of the model's toes PHYSICAL THERAPY
PAUL R. MANSKE, MD, and PEGGY GLEESON, BS
A rehabilitation program which has been used successfully in improving the postoperative range of motion of patients undergoing total knee arthroplasty is outlined. The specific objectives are strong quadriceps setting, straight leg raising, flexion of the knee to at least 90 degrees, and extension of the knee to 0 degrees. The program emphasizes the importance of early institution of exer cises and early ambulation.
The development of the first hinge-type total knee replacement prosthesis by Waldius in 1951 and the first resurfacing type of total knee replacement prosthesis by Gunston in 1968 proved to be major contributions to re constructive surgery of the arthritic knee. 1,2 Since then, over 300 different models have been developed based on the original designs of Waldius and Gunston. 3 Although the primary indication for total knee surgery is the presence of pain, patients may also have varus or valgus deformities and limited motion, both in flexion and extension. Fortunately, about 85 percent to 95 percent of patients have significant relief of pain following total knee replacement surgery regardless of the model used. 4-7 Most knees are stable post operatively, indicating adequate correction of the varus or valgus deformities. Little success has been reported in increasing range of motion postoperatively, however. Gunston reported no change in range of mo tion. 8 Ilstrup reported an average improve ment of 7.3 degrees of motion in patients with rheumatoid arthritis and no change in patients Dr. Manske is Assistant Professor of Orthopedic Surgery, Divi sion of Orthopedic Surgery, Dept of Surgery, Washington Univer sity School of Medicine, 4960 Audubon Ave, St. Louis, MO 63110. Ms. Gleeson is Staff Physical Therapist, Irene Walter Johnson Institute of Rehabilitation, Washington University School of Medi cine, 509 S Euclid Ave, St. Louis, MO 63110.
Volume 57 / Number 8, August 1977
with degenerative arthritis following polycen tric total knee arthroplasty. 4 The Mayo Clinic reported a 2 degree loss of motion following geometric total knee arthroplasty. 5 The duo condylar knee replacement averaged 1 degree improvement in the arc of motion. 6 Marmour reported a 1 degree loss of motion using the modular knee replacement. 7 A review of 56 consecutive polycentric total knee arthroplasties reported by the senior au thor indicated a statistically significant im provement in postoperative range of motion. 9 Patients with rheumatoid arthritis had an aver age increase in the motion arc of 18.5 degrees, those with degenerative arthritis an average increase of 8.7 degrees. The combined results of all patients in the series indicate an average increase of 13.7 degrees. The improvement was noted both in flexion and in extension; 96 percent of the operated knees had more than 90 degrees of flexion and 63 percent had greater than 110 degrees of flexion postopera tively. Only 2 patients (3.6%) lacked more than 15 degrees of extension. Improved motion is related to the design of the prosthesis and to careful surgical tech nique. We believe, however, that the vigorous postoperative exercise program which we use is of utmost importance in obtaining these re sults. This article outlines our rehabilitation program following total knee replacement sur915
Downloaded from https://academic.oup.com/ptj/article-abstract/57/8/915/4558978 by University of Texas at Dallas user on 03 February 2019
Rehabilitation Program Following Polycentric Total Knee Arthroplasty
gery. References about such programs are lim ited. 10-12 REHABILITATION PROGRAM
916
Downloaded from https://academic.oup.com/ptj/article-abstract/57/8/915/4558978 by University of Texas at Dallas user on 03 February 2019
The rehabilitation program begins in the preoperative period. In order to allay the pa tient's apprehension, the operative procedure and the postoperative exercise program are explained to him as simply and clearly as possi ble by the surgeon and the physical therapist. The patient is specifically instructed in quadri ceps setting and straight leg raising exercises. In the postoperative period, the patient is seen by the physical therapist twice daily and encouraged by the nursing staff to exercise throughout the day. The importance of each exercise is explained to the patient with the encouragement that best results are obtained with independent hourly exercising. The entire exercise program takes place in the familiar environment of the patient's room and on the hospital ward. The appropriate time for the administration of pain medication may be de termined by the physical therapist, the nurse, or the patient to ensure maximum voluntary effort during exercise sessions. A long leg cast is applied in the operating room to prevent the development of early knee flexion contracture. Forty-eight hours later, the cast is bivalved and the posterior half of the cast serves as a splint which is worn only at night to maintain complete knee extension. After the cast has been removed, three distinct exercises are emphasized: 1) quadriceps setting and straight leg raising, 2) flexion of the knee to at least 90 degrees, and 3) active extension of the knee to 0 degrees. Quadriceps Setting and Straight Leg Raising. The most important aspect of the initial exer cise program is restoration of quadriceps func tion. Straight leg raising is encouraged in the immediate postoperative period while the pa tient is still in the recovery room. This exercise is stressed during the first 48 hours while the knee is immobilized in a cast. Straight leg rais ing is frequently easier to accomplish while in the cast than after the cast has been removed, because the cast is holding the knee in exten sion and is in effect substituting for the quadri ceps muscle. If the patient is unable to actively raise his leg, the therapist passively lifts it and asks the patient to hold that position. If the patient is still unable to initiate knee extension, he is
placed on his unoperated side, abducting and flexing the hip while keeping the operated knee extended. He then rolls back to the su pine position and attempts to perform hip flex ion and knee extension. Flexion. Active and active-assisted knee flexion is encouraged from the time the cast is removed. The patient begins by simply flexing and extending the hip in the supine position and allowing his heel to slide along the surface of the bed. An exercise sling is fashioned and attached to the overhead bar on the bed. The sling, consisting of felt and stockinette, is placed under the patient's thigh proximal to the knee. A rope is attached to it and passed through a pulley on the overhead bar. A small sandbag is attached to the opposite end of the rope. By pulling on the sandbag, the patient passively raises the thigh and assists the knee in flexion. For patients with arthritic deformities of the hands and wrists, another felt sling may be attached in place of the sandbag. The pa tient slips his forearms through this second sling and pulls. Knee flexion exercises are performed with the patient sitting in a chair. With the foot planted firmly on the floor, the patient gently slides his buttocks forward toward the edge of the chair, flexing his knee as much as possible. After holding this position for a few seconds, he slides backwards in the chair. This exercise can also be performed in a wheelchair. After planting his foot firmly, he rolls the wheelchair forward to obtain maximum knee flexion and then rolls the chair backward. Ninety degrees of flexion is usually attained within 12 days after surgery. When this range is not obtained, passive manipulation into flex ion under general anesthesia by the surgeon may be necessary. Only 3.6 percent of the knee arthroplasties in our series required such manipulation. Extension. In his enthusiasm to achieve max imum knee flexion and to regain his quadriceps muscle strength, the patient tends to overlook the importance of knee extension to 0 degrees. In order to prevent flexion contractures, the foot of the bed is always flat and at no time is a pillow allowed underneath the operated knee. If the patient is unable to passively extend his knee to 0 degrees, a small pillow or rolled towel is placed under the patient's heel when he is supine. The patient is instructed to flatten the popliteal fossa against the bed. When the patient is sitting in a chair, a stool is placed PHYSICAL THERAPY
Volume 57 / Number 8, August 1977
patient has a very strong quadriceps muscle we do not encourage use of more than eight pounds of weight. DISCUSSION
Daily activites of arthritic patients are fre quently limited by pain, varus or valgus de formity, or inadequate range of motion. The relief of pain and the correction of the deform ity are dependent upon the design of the pros thesis and the operative technique of the sur geon; the improvement of knee motion is de pendent upon the rehabilitation program. Al though we are not trying to minimize the im portance of a stable and pain-free total knee arthroplasty, we believe that the significance of increased range of motion has been overlooked by surgeons and therapists. The importance of knee flexion to 90 de grees is well accepted and some authors believe that 110 degrees of flexion is necessary. 13 We believe that this amount of flexion can only be attained with a vigorous exercise program which includes quadriceps setting in the imme diate postoperative period and range of motion exercises beginning the second rather than the seventh postoperative day. 11,12 The impor tance of knee extension to less than 15 degrees has been documented. 14 Patients, however, are frequently so concerned with bending the knee and regaining strength that they tend to forget the importance of complete knee extension to 0 degrees. We believe that the patient benefits physio logically and psychologically from rapid reha bilitation. Consequently, we emphasize early ambulation with external support and weight bearing as tolerated. We have not experienced difficulties with wound management which could be attributed to early motion or early ambulation. Our rehabilitation program following total knee arthroplasty has been successful in terms of patient satisfaction, as well as improvement in knee stability, range of motion, and relief of pain. We consider the rehabilitation program to be an essential part of total knee arthro plasty and advise that it be pursued vigorously. REFERENCES 1. Waldius B: Arthroplasty of the knee using an acrylic pros thesis. Acta Orthop Scand 23:121, 1953 2. Gunston FH: Polycentric knee arthroplasty: Prosthetic simula tion of normal knee movement. J Bone Joint Surg 53 [Br]:272277, 1971
917
Downloaded from https://academic.oup.com/ptj/article-abstract/57/8/915/4558978 by University of Texas at Dallas user on 03 February 2019
under his foot and similar exercises are carried out. The patient is also instructed to passively extend the knee by manually exerting down ward pressure over the patella. Ambulation. When the patient is independ ently able to straight leg raise and has at least 60 degrees of knee flexion, ambulation with a walker is instituted. The patient is allowed to bear full weight on the operated extremity as tolerated. Patients usually experience very lit tle of the severe arthritic pain which they had preoperatively. They may complain of inci sional pain which is more tolerable than the deep pain. A normal gait is encouraged, in cluding equal stride length, full knee extension in the stance phase, and knee flexion during the swing-through phase. Most patients are in structed in stair-climbing techniques, especially if they have stairs at home. Before discharge, many of our patients have progressed to ambu lating with a standard cane, although patients are not necessarily encouraged to discontinue use of the walker. Posthospitalization. Patients are hospitalized an average of 3 weeks. At the time of dis charge, the exercise program is reviewed and the patient is instructed to perform each exer cise at home on a daily basis. Unless problems develop, he is not seen as an outpatient by the physical therapist until his regularly scheduled office visit 6 weeks after discharge. He is en couraged, however, to call the surgeon or the therapist if any difficulties or questions arise. The patient is seen in a follow-up clinic by the surgeon and the physical therapist at 6 weeks, 3 months, and 9 months, and at yearly inter vals thereafter.. At 6 weeks, many patients have discontin ued using the external support. The patient is questioned about the presence of pain, the use of external support, and difficulties in daily activities such as ambulating, stair climbing, or rising from a sitting position. The patient's gait is evaluated and examination of the stability and range of motion of the knee is made. By 3 months, the patient has usually pro gressed satisfactorily and is allowed to begin light quadriceps resistance exercises. He is in structed to sit on a table or counter and extend the knee with weights suspended from the an kle. Starting with one pound and gradually increasing the weight to a maximum of eight pounds, the patient extends and holds his knee in extension for 10 seconds 20 times both in the morning and in the evening. Unless the
3. Ewold FC: Metal to plastic total knee replacement. Orthop Clinic North Am 6:811-821, 1975 4. Ilstrup OM, Combs JJ, Bryan RS, et al: A statistical evalua tion of polycentric total knee arthroplasties. Clin Orthop 120:18-26, 1976
6. Ranawat CS, Insall J, Shim J: Duo-condylar knee arthro plasty. Clin Orthop 120:76-82, 1976 7. Marmour L: The modular (Marmour) knee. Clin Orthop 120:86-94, 1976 8. Gunston FH: Complication of polycentric knee arthroplasty. Clin Orthop 120:11-17, 1976
Forest Town Boot JAMES J. CRAIG, MB, B Ch, Dip Surg, and ANNA MATHIAS, BSc
The most common deformity of the feet in children with cerebral palsy is that of equinus, caused by an increase in muscle tone as a result of an exaggerated positive supporting reaction. Associated with the equinus may be a varus or a valgus deformity, and the deformity may be present in either a nonweightbearing or weightbearing position. The purpose of the Forest Town Boot is to enable a child with an equinus deformity of the foot because of an overactive positive support ing reaction to stand and walk with a planti grade foot (Figs. 1 and 2). The effect of the boot is to prevent shortening of the tendo Achilles and the long flexor muscles of the toes and to allow lengthening of the triceps surae while preventing lengthening of the dorsiflexor muscles of the foot. The most important thera peutic effect of the boot is the continuous stretch on the triceps surae muscle group (par ticularly the soleus muscle) and the long toe flexors, producing a lengthening of these two muscle groups. The static stretch of the soleus muscles and calcaneal weight bearing may be responsible for the reflex facilitation of the Dr. Craig is Principal Orthopaedic Surgeon, Orthopaedic De partment, University of the Witwatersrand, Medical School, and Johannesburg Hospital, South Africa. Mrs. Mathias is Chief Physiotherapist, Johannesburg Hospital, Private Bag X39, Johannesburg 2000, South Africa. This article was adapted from a paper presented by Dr. Craig at the Annual Meeting of the American Academy of Cerebral Palsy in New Orleans in 1975.
918
Downloaded from https://academic.oup.com/ptj/article-abstract/57/8/915/4558978 by University of Texas at Dallas user on 03 February 2019
5. Skolnick MD, Coventry MB, Ilstrup OM: Geometric total knee arthroplasty. J Bone Joint Surg 58 [Am]:749-753, 1976
9. Manske PR, DeBender JJ: Polycentric total knee arthroplasty. South Med J, to be published 10. Convery RF, Beber CA: Total knee arthroplasty, indications, evaluation, and postoperative management. Clin Orthop 94:42-49, 1973 11. Waters EA: Physical therapy management of patients with total knee replacement. Phys Ther 54:936-942, 1974 12. Paradis D, Hamlin C: Geometric and polycentric knee pros thesis. Phys Ther 53:762-768, 1973 13. Laubenthal KN, Smidt GL, Kettlekamp DB: A quantitative analysis of knee motion during activities of daily living. Phys Ther 52:34-42, 1972 14. Perry J, Antonelli D, Ford A: Analysis of knee joint forces during flexed knee stance. J Bone Joint Surg 57 [Am]:961967, 1975
dorsiflexors of the foot. 1 In our experience, the Forest Town Boot, used postoperatively, helps to reduce the recurrence rate of deformity. 2-4 CASTING AND MANUFACTURE OF THE FOREST TOWN BOOT
1. For casting, the physical therapist holds the child on her lap, facing the orthotist. 2. Stockinette is applied first, extending to just below the knee, with an excess of ap proximately 20 cm at the toes. 3. The therapist keeps the patient's knee in 90 degrees of flexion to prevent a sudden ex tension of the knee and foot. The foot is held in 10 degrees of dorsiflexion and slight varus. Proximal pressure applied with the excess stockinette holds the toes in a posi tion of maximal dorsiflexion and the foot, ankle, and knee positions are maintained during the casting procedure. The orthotist, while applying and molding the plaster bandages must ensure that the ankle and the foot positions are maintained and that the foot is not allowed to go into valgus (Fig. 3). 4. After the positive model has been made from the removed cast, the bony promi nences of the ankle must be well built up and the toes of the mold extended by 1.25 cm and given a round aspect. (The reason for extending the length of the model's toes PHYSICAL THERAPY
