International Orthopaedics (SICOT) (2015) 39:27–33 DOI 10.1007/s00264-014-2554-0
ORIGINAL PAPER
Total hip arthroplasty with subtrochanteric osteotomy in neglected dysplastic hip Eid Ahmed & El-Ganzoury Ibrahim & Bassiony Ayman
Received: 17 July 2014 / Accepted: 23 September 2014 / Published online: 11 October 2014 # SICOT aisbl 2014
Abstract Purpose Total hip arthroplasty (THA) in the presence of developmental dysplasia of the hip (DDH) presents many challenges to the reconstructive surgeon. The complexity of femoral and acetabular anatomy in these cases makes standard reconstruction technically challenging. Restoring the anatomic centre of hip rotation may require femoral osteotomy. The aim of this study was to determine the rate of union, complications and functional results in a series of patients with Crowe IV dysplastic hips who underwent cementless THA and simultaneous subtrochanteric oblique osteotomy. Methods A retrospective study was designed in a series of 13 patients (14 hips) with Crowe IV DDH who underwent cementless THA and simultaneous subtrochanteric oblique osteotomy at a mean age of 37 years. Patients were reviewed clinically and radiographically with a minimum follow-up of two years. Complications were noted. Harris Hip Score (HHS) was recorded pre-operatively and at six and 12 months postoperatively. Results Union occurred in 14 of 14 femora (100 %). The overall revision rate was 14 % (7 % femoral, 7 % acetabular). No dislocations necessitated further surgery. No patient had intraoperative femoral fracture, sciatic nerve injury, infection or deep venous thrombosis. Mean HHS improved from 42 preoperatively to 79 at 6 months and 86 at 12 months. Conclusion Combined subtrochanteric femoral osteotomy and cementless THA is technically demanding and proved to be safe and effective in femoral shortening for treatment of Crowe IV DDH. Keywords Dysplastic hip . Osteotomy . Subtrochanteric . Arthroplasty . Crowe IV E. Ahmed (*) : E.4 cm [11, 12], leading to difficulty in reducing the hip and a major risk of neurologic traction injury [2], particularly where there is scarring from previous surgery, which increases the risk of direct or indirect neurologic injury [11]. On the femoral side, computed tomography (CT) studies have demonstrated that dysplastic femurs had consistently increased anteversion, shorter necks and decreased intramedullary canal size than nondysplastic femurs and straight contour and that the anterior bow of the femur displaced further distally with increasing degree of dysplasia [13]. The decreased canal width and thinner cortical diameters in dysplastic hips also may make them more prone to fracture [14] and adds to the difficulty of obtaining stable implantation of an adequately sized femoral component [15–17]. To address these difficulties during THA for severe dysplasia, many surgeons advocate performing subtrochanteric osteotomy, of which different types—either transverse, oblique chevron or T-shaped—have been well documented
28
International Orthopaedics (SICOT) (2015) 39:27–33
with good clinical results [18–25], but nonunion and complexity in performance remain the major concerns in the procedure [18, 26]. Progressive osteotomy at the femoral neck with greater trochanteric osteotomy [27], distal femoral osteotomy [15] and lesser trochanteric osteotomy has been reported in previous studies [28]. Most published studies reporting THA combined with subtrochanteric osteotomy in DDH used cementless femoral components and reported high rates of union and major improvements in the postoperative Harris Hip Score (HHS) [4, 16, 18, 20, 29–35]; cemented femoral components are rarely used, although similar rates of union and survivorship are reported compared with cementless components [6, 36–40]. The aim of this study was to determine union rate, complications and early HHS in a series of cementless THA and simultaneous subtrochanteric oblique osteotomy in 13 patients (14 hips) with Crowe IV dysplastic hips.
Patients and methods This was a prospective study of 13 patients (14 hips) who underwent primary cementless THA with simultaneous subtrochanteric osteotomy between 2006 and 2012. The indication for surgery was painful osteoarthritis secondary to severe DDH (Crowe Grade IV [2]) in all cases. The mean age at surgery was 37 (range, 27–54) years. All patients were last followed up between two and eight years after surgery (mean, 4.75 years). Subtrochanteric osteotomy was performed to shorten the femur in all cases; the average length of bone removed was 2 cm (range, 1.5–2.5 cm). All operations were performed using cementless femoral and acetabular components (Trilogy acetabular system, FMT stem, Zimmer, Warsaw, IN, USA). A posterior approach was used, with distal extension to access the proximal femoral shaft. The sciatic nerve was identified and carefully protected but not formally dissected. The true acetabulum was identified by following the ligamentum teres and confirmed by image intensifier; the acetabulum was then prepared in the standard manner with a structural femoral head autograft to provide adequate superior coverage of the cup where necessary, but it was performed only if 50–70 % of the trial was covered by the acetabulum [nine hips (64.3 %)]. The acetabular component was then implanted. On the femoral side, a total capsulectomy was performed, the iliopsoas tendon released and the gluteal sling kept intact. The femoral canal was opened by straight reamer and prepared in the standard manner by rasping. The femoral component with the largest offset, which best fit the femur, was chosen. With the trial rasp in place, traction was then applied to the femur for trial reduction, which usually proved impossible. The rasp was removed, and a short oblique osteotomy
Fig. 1 a Femoral neck osteotomy; b acetabular component implantation in true acetabulum and femoral canal preparation; c short oblique subtrochanteric osteotomy is performed, femoral rasp replaced into proximal fragment, which is reduced into the acetabulum, and amount of overlap between proximal and distal fragments is determined to identify bone length to be resected; d after bone resection equal in length to amount of overlap, proximal and distal fragments are reduced together
was performed just distal to the lesser trochanter. The rasp was replaced into the proximal fragment only, which was reduced to ensure the abductors allowed normal positioning of the femoral component. An abductor release or trochanteric slide was not required in any case in this series. Traction was applied to the distal fragment, and the amount of overlap between the proximal and distal fragments was noted, reflecting the corresponding length of bone to be resected from the distal fragment to allow reduction of the final construct. After bone resection, the proximal and distal fragments were reduced and the appropriate femoral trial introduced
Fig. 2 After bone resection, proximal and distal fragments are reduced; final component with compression of osteotomy site after bone resection
International Orthopaedics (SICOT) (2015) 39:27–33
29
Fig. 3 a Autologous morselised bone graft; b resected bone is split longitudinally into two halves and placed around the osteotomy site as additional strut bone graft and fixed with cerclage wires
across the osteotomy, which was compressed with bonereduction forceps (Figs. 1 and 2). Trial reduction into the acetabulum and assessment of stability was confirmed. The definitive femoral component was then implanted, the osteotomy site packed with an autologous morselised bone graft and resected bone from the distal fragment split longitudinally into two to four fragments and placed around the osteotomy site as additional strut bone graft and fixed with cerclage wires (Fig. 3). Postoperatively, patients were allowed to partially weight bear for the first six weeks with the aid of a walking frame or two walking sticks and were reviewed in the outpatient clinic at six weeks, three months, six months and 12 months after surgery. HHS was recorded pre-operatively and at six and 12 months postoperatively. At each follow-up visit, the patients were assessed clinically and radiographically by anteroposterior (AP) and lateral radiographs. Rate of osteotomy union and complications were recorded. Union was defined by the presence of mature bone bridging the osteotomy on at least three of four cortices as seen on AP and lateral radiographs (Fig. 4). Complications were defined as deep infection (requiring reoperation), dislocation, neurologic injury (temporary or permanent), intra-operative fracture, periprosthetic fracture and revision for any reason.
(7 %) after 1.5 years using a cementless tantalum cup (Zimmer), with no further revision at last follow-up at three years. The femoral head was reduced into the true acetabulum for each hip. There was no sciatic nerve palsy, either transient or permanent, infection, dislocation or periprosthetic fracture during the follow-up period. No patient developed deep venous thrombosis. Mean leg length discrepancy (LLD) for 12 patients with unilateral dysplastic hip (12 hips) decreased from 4.25 cm (range, 0–7) pre-operatively to 0.7 cm (range, 0–2.5) postoperatively. All patients had positive Trendelenburg signs preoperatively. Five hips (35.7 %) became negative for Trendelenburg sign, which was positive but markedly reduced in seven hips (50 %), and two hips (14.3 %) continued to show the sign until the last follow-up. HHS improved from 42 (range, 24–59) pre-operatively to 79 (range, 62–89) at six months and 86 (range, 68–92) at 12 months (Table 2).
Results Fourteen primary hips in 13 patients (seven women, six men), mean age 37 (range 27–54) years, were operated upon. The mean follow-up period was 4.75 (range, two to eight) years. No patient was lost to follow-up. All osteotamies united (100 %); there were two complications (14 %) (Table 1). Two revisions were necessary for aseptic loosening (14 %): one for femoral component loosening (7 %) after two years, which was revised by cementless long-stem femoral component (Wagner stem, Zimmer) with no further revision at last follow-up at two years after revision; the other was revised for acetabular component loosening
Fig. 4 a Pre-operative anteroposterior (AP) radiograph of pelvis in 46year-old man with neglected developmental dysplasia of the hip (DDH) Crowe IV; b 6 months postoperative image showing bridging callus at osteotomy site after total hip replacement (THR) with subtrochanteric osteotomy
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International Orthopaedics (SICOT) (2015) 39:27–33
Table 1 Major complications
Complications
Total
Infection Dislocation Nonunion of osteotomy Sciatic nerve palsy Aseptic loosening
0 0 0 0 2
Intraoperative femoral fracture Deep venous thrombosis
0 0
Discussion Crowe type IV DDH presents a challenge for THA. In dealing with such cases, the surgeon should anticipate being faced with problems on both the acetabular and femoral sides. As regards the acetabulum, there are usually segmental defects that might be superior, anterior or posterior. The acetabulum is usually excessively anteverted, shallow and small, reflected by the small distance between the anterior and posterior walls, which presents a difficulty in reaching proper cup size with adequate bony coverage. On the femoral side, there is usually excessive anteversion, and the femoral canal is usually narrow, with pencil-like cortices. Another important issue in neglected dysplastic hips is soft-tissue contracture that results from the longstanding pathology. There is shortening of the neurovascular bundle, with general decrease in tissue excursion with subsequent difficulty in reducing the head in the true acetabulum and subsequent difficulty in restoring limb length without putting the sciatic nerve at risk of injury. In order to address these problems, femoral shortening osteotomy, with
its different types, was used to facilitate restoring hip centre and leg length without sciatic nerve compromise. The purpose of this study was to determine union rate, complications and HHS in a series of patients undergoing cementless THA and simultaneous subtrochanteric short oblique osteotomy for neglected DDH. Our union rate of 100 % is similar to reported results [20, 29, 31, 34] and compare favourably with other studies using THA with subtrochanteric osteotomy and cementless stem [4, 16, 18, 30, 32, 33, 35]. Total revision rate in our study was 14 % (two cases) for aseptic loosening, which compare favourably with revision rates in other studies [4, 16, 18, 20, 29, 31, 33, 34] and inferior to results reported by Sener et al. [30], Onodera et al. [32], and Nagoya et al. [35]. We had no complications of dislocation, infection, sciatic nerve palsy, intraoperative femoral fracture or deep vein thrombosis (Table 3). Absence of dislocation in this series can be explained by proper component orientation, restoring abductor lever arm by placing the cup in the true acetabulum and restoring the anatomical centre of hip rotation. In addition the subtrochanteric osteotomy allowed internal rotation of the proximal fragment, if needed, for stability during trial assessment. Using the posterior approach in this series may counteract the tendency towards anterior dislocation due to the excessive femoral anteversion found in neglected dysplastic hips. Osteotomy union occurred in all cases, and may be attributed to many factors: First, oblique osteotomy used in this study has two main advantages: (1) it provides rotational stability at the osteotomy site, and (2) it increases the surface area at the osteotomy site, which in turn increases the union rate. Also, the use of bone grafts at the osteotomy
Table 2 Demography, leg-length discrepancy (LLD), and Harris Hip Score (HHS) No.
Sex
Age
FU (years)
Preop LLD (cm)
Postop LLD (cm)
Preop HHS
HHS 6 months postop
HHS 12 months postop
1 2 3 4 5
F M F M F
29 27 38 45 27
3 2 4 5 8
4 6 7 0 5
0 1.5 2.5 0 1
57 33 24 33 54
89 73 62 83 87
92 81 68 87 90
6 7 8 9 10 11 12 13 14
F M F F M M F M F
46 54 39 39 37 28 30 49 36
7 4.5 6 6 4.5 4 3 4 5.5
3 6 – – 3 5 5 3 4
0 1.5 – – 0 1 1 0 0
56 29 33 35 53 31 35 57 59
83 68 68 81 86 73 76 88 89
86 81 83 87 90 87 88 92 90
FU follow-up, Preop pre-operative, Postop postoperative
2 (10 %) 5 (18 %) 0 0 0 0 0 0 0 0 4 (14 %) 0 2 (10 %) 4 (14 %) 1 (7 %) 2 (10 %) 7 (25 %) 2 (14 %) 19 (95 %) 26 (93 %) 14 (100 %) Cementless Cementless Cementless 8.1 (4–11.5) 4.8 (2–13.4) 4.75 (2–8) 20 28 14 Nagoya et al. 2009 [35] Krych et al. 2009 [18] Current study
55 (44–69) 48 (30–72) 37 (27–54)
5 (11 %) 0 2 (22 %) 0 0 6 (43 %) 4 (6 %) 3 (13 %) 0 NS 0 0 3 (11 %) 0 NS 5 (7 %) 0 0 1 (2 %) 0 0 2 (7 %) 0 0 0 0 0 2 (4 %) 0 1 (11 %) 0 3 (14 %) 1 (7 %) 3 (4 %) 1 (4 %) 4 (18 %) 3 (7 %) 0 1 (11 %) 2 (7 %) 2 (9 %) 1 (7 %) 5 (7 %) 3 (13 %) 0 8 (17 %) 1 (14 %) 2 (22 %) 2 (7 %) 5 (23 %) 1 (7 %) 29 (43 %) 4 (17 %) 4 (18 %) 44 (96 %) 7 (100 %) 9 (100 %) 26 (93 %) 22 (100 %) 13 (93 %) 58 (95 %) 21 (88 %) 23 (100 %) cementless cementless Cementless Cementless Cementless Cementless Cementless Cementless Cementless 3.2 (1–5.9) 2.7 (0.3–6) 4.7 (0.5–7.2) 4 (0.6–7.7) 2.1 (0.7–7.8) 5 (3–7.9) 12.3 (9–15) 4.7 (2–7.6) 8 (5–14) 46 7 9 28 22 14 61 24 23 Paavilainen et al. 1990 [16] Becker et al. 1995 [20] Bruce et al. 2000 [29] Sener et al. 2002 [30] Carlsson et al. 2003 [31] Onodera et al. 2006 [32] Eskelinen et al. 2006 [4] Park et al. 2007 [33] Bernasek et al. 2007 [34]
50 (22–78) 61 (48–72) 53 (26–77) 43 (26–64) 55 (23–80) 55 (44–69) 54 (29–74) 49 (20–66) 43 (17–67)
Femoral revisions (%) Total revisions (%) Union (%) Stem type Mean follow-up (years) No. patients
Mean age (years, range)
31
Author
Table 3 Overview of previous studies of total hip arthroplasty (THA) with subtrochanteric osteotomy using cementless femoral stem
Dislocations (%)
Deep infections (%)
Neurologic injuries (%)
Intraoperative femoral fracture (%)
International Orthopaedics (SICOT) (2015) 39:27–33
site, both morselised and structural, and absence of infection are other factors in promoting union. Finally, absence of any retained hardware from previous surgeries may be another factor improving the union rate, as retained metalwork has been proved to add specific difficulties in performing THA [41]. There was no sciatic nerve palsy, either transient or permanent, in our series. Femoral lengthening by >4 cm increases the incidence of nerve palsy, and various authors have recommended lengthening the femur by
ORIGINAL PAPER
Total hip arthroplasty with subtrochanteric osteotomy in neglected dysplastic hip Eid Ahmed & El-Ganzoury Ibrahim & Bassiony Ayman
Received: 17 July 2014 / Accepted: 23 September 2014 / Published online: 11 October 2014 # SICOT aisbl 2014
Abstract Purpose Total hip arthroplasty (THA) in the presence of developmental dysplasia of the hip (DDH) presents many challenges to the reconstructive surgeon. The complexity of femoral and acetabular anatomy in these cases makes standard reconstruction technically challenging. Restoring the anatomic centre of hip rotation may require femoral osteotomy. The aim of this study was to determine the rate of union, complications and functional results in a series of patients with Crowe IV dysplastic hips who underwent cementless THA and simultaneous subtrochanteric oblique osteotomy. Methods A retrospective study was designed in a series of 13 patients (14 hips) with Crowe IV DDH who underwent cementless THA and simultaneous subtrochanteric oblique osteotomy at a mean age of 37 years. Patients were reviewed clinically and radiographically with a minimum follow-up of two years. Complications were noted. Harris Hip Score (HHS) was recorded pre-operatively and at six and 12 months postoperatively. Results Union occurred in 14 of 14 femora (100 %). The overall revision rate was 14 % (7 % femoral, 7 % acetabular). No dislocations necessitated further surgery. No patient had intraoperative femoral fracture, sciatic nerve injury, infection or deep venous thrombosis. Mean HHS improved from 42 preoperatively to 79 at 6 months and 86 at 12 months. Conclusion Combined subtrochanteric femoral osteotomy and cementless THA is technically demanding and proved to be safe and effective in femoral shortening for treatment of Crowe IV DDH. Keywords Dysplastic hip . Osteotomy . Subtrochanteric . Arthroplasty . Crowe IV E. Ahmed (*) : E.4 cm [11, 12], leading to difficulty in reducing the hip and a major risk of neurologic traction injury [2], particularly where there is scarring from previous surgery, which increases the risk of direct or indirect neurologic injury [11]. On the femoral side, computed tomography (CT) studies have demonstrated that dysplastic femurs had consistently increased anteversion, shorter necks and decreased intramedullary canal size than nondysplastic femurs and straight contour and that the anterior bow of the femur displaced further distally with increasing degree of dysplasia [13]. The decreased canal width and thinner cortical diameters in dysplastic hips also may make them more prone to fracture [14] and adds to the difficulty of obtaining stable implantation of an adequately sized femoral component [15–17]. To address these difficulties during THA for severe dysplasia, many surgeons advocate performing subtrochanteric osteotomy, of which different types—either transverse, oblique chevron or T-shaped—have been well documented
28
International Orthopaedics (SICOT) (2015) 39:27–33
with good clinical results [18–25], but nonunion and complexity in performance remain the major concerns in the procedure [18, 26]. Progressive osteotomy at the femoral neck with greater trochanteric osteotomy [27], distal femoral osteotomy [15] and lesser trochanteric osteotomy has been reported in previous studies [28]. Most published studies reporting THA combined with subtrochanteric osteotomy in DDH used cementless femoral components and reported high rates of union and major improvements in the postoperative Harris Hip Score (HHS) [4, 16, 18, 20, 29–35]; cemented femoral components are rarely used, although similar rates of union and survivorship are reported compared with cementless components [6, 36–40]. The aim of this study was to determine union rate, complications and early HHS in a series of cementless THA and simultaneous subtrochanteric oblique osteotomy in 13 patients (14 hips) with Crowe IV dysplastic hips.
Patients and methods This was a prospective study of 13 patients (14 hips) who underwent primary cementless THA with simultaneous subtrochanteric osteotomy between 2006 and 2012. The indication for surgery was painful osteoarthritis secondary to severe DDH (Crowe Grade IV [2]) in all cases. The mean age at surgery was 37 (range, 27–54) years. All patients were last followed up between two and eight years after surgery (mean, 4.75 years). Subtrochanteric osteotomy was performed to shorten the femur in all cases; the average length of bone removed was 2 cm (range, 1.5–2.5 cm). All operations were performed using cementless femoral and acetabular components (Trilogy acetabular system, FMT stem, Zimmer, Warsaw, IN, USA). A posterior approach was used, with distal extension to access the proximal femoral shaft. The sciatic nerve was identified and carefully protected but not formally dissected. The true acetabulum was identified by following the ligamentum teres and confirmed by image intensifier; the acetabulum was then prepared in the standard manner with a structural femoral head autograft to provide adequate superior coverage of the cup where necessary, but it was performed only if 50–70 % of the trial was covered by the acetabulum [nine hips (64.3 %)]. The acetabular component was then implanted. On the femoral side, a total capsulectomy was performed, the iliopsoas tendon released and the gluteal sling kept intact. The femoral canal was opened by straight reamer and prepared in the standard manner by rasping. The femoral component with the largest offset, which best fit the femur, was chosen. With the trial rasp in place, traction was then applied to the femur for trial reduction, which usually proved impossible. The rasp was removed, and a short oblique osteotomy
Fig. 1 a Femoral neck osteotomy; b acetabular component implantation in true acetabulum and femoral canal preparation; c short oblique subtrochanteric osteotomy is performed, femoral rasp replaced into proximal fragment, which is reduced into the acetabulum, and amount of overlap between proximal and distal fragments is determined to identify bone length to be resected; d after bone resection equal in length to amount of overlap, proximal and distal fragments are reduced together
was performed just distal to the lesser trochanter. The rasp was replaced into the proximal fragment only, which was reduced to ensure the abductors allowed normal positioning of the femoral component. An abductor release or trochanteric slide was not required in any case in this series. Traction was applied to the distal fragment, and the amount of overlap between the proximal and distal fragments was noted, reflecting the corresponding length of bone to be resected from the distal fragment to allow reduction of the final construct. After bone resection, the proximal and distal fragments were reduced and the appropriate femoral trial introduced
Fig. 2 After bone resection, proximal and distal fragments are reduced; final component with compression of osteotomy site after bone resection
International Orthopaedics (SICOT) (2015) 39:27–33
29
Fig. 3 a Autologous morselised bone graft; b resected bone is split longitudinally into two halves and placed around the osteotomy site as additional strut bone graft and fixed with cerclage wires
across the osteotomy, which was compressed with bonereduction forceps (Figs. 1 and 2). Trial reduction into the acetabulum and assessment of stability was confirmed. The definitive femoral component was then implanted, the osteotomy site packed with an autologous morselised bone graft and resected bone from the distal fragment split longitudinally into two to four fragments and placed around the osteotomy site as additional strut bone graft and fixed with cerclage wires (Fig. 3). Postoperatively, patients were allowed to partially weight bear for the first six weeks with the aid of a walking frame or two walking sticks and were reviewed in the outpatient clinic at six weeks, three months, six months and 12 months after surgery. HHS was recorded pre-operatively and at six and 12 months postoperatively. At each follow-up visit, the patients were assessed clinically and radiographically by anteroposterior (AP) and lateral radiographs. Rate of osteotomy union and complications were recorded. Union was defined by the presence of mature bone bridging the osteotomy on at least three of four cortices as seen on AP and lateral radiographs (Fig. 4). Complications were defined as deep infection (requiring reoperation), dislocation, neurologic injury (temporary or permanent), intra-operative fracture, periprosthetic fracture and revision for any reason.
(7 %) after 1.5 years using a cementless tantalum cup (Zimmer), with no further revision at last follow-up at three years. The femoral head was reduced into the true acetabulum for each hip. There was no sciatic nerve palsy, either transient or permanent, infection, dislocation or periprosthetic fracture during the follow-up period. No patient developed deep venous thrombosis. Mean leg length discrepancy (LLD) for 12 patients with unilateral dysplastic hip (12 hips) decreased from 4.25 cm (range, 0–7) pre-operatively to 0.7 cm (range, 0–2.5) postoperatively. All patients had positive Trendelenburg signs preoperatively. Five hips (35.7 %) became negative for Trendelenburg sign, which was positive but markedly reduced in seven hips (50 %), and two hips (14.3 %) continued to show the sign until the last follow-up. HHS improved from 42 (range, 24–59) pre-operatively to 79 (range, 62–89) at six months and 86 (range, 68–92) at 12 months (Table 2).
Results Fourteen primary hips in 13 patients (seven women, six men), mean age 37 (range 27–54) years, were operated upon. The mean follow-up period was 4.75 (range, two to eight) years. No patient was lost to follow-up. All osteotamies united (100 %); there were two complications (14 %) (Table 1). Two revisions were necessary for aseptic loosening (14 %): one for femoral component loosening (7 %) after two years, which was revised by cementless long-stem femoral component (Wagner stem, Zimmer) with no further revision at last follow-up at two years after revision; the other was revised for acetabular component loosening
Fig. 4 a Pre-operative anteroposterior (AP) radiograph of pelvis in 46year-old man with neglected developmental dysplasia of the hip (DDH) Crowe IV; b 6 months postoperative image showing bridging callus at osteotomy site after total hip replacement (THR) with subtrochanteric osteotomy
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International Orthopaedics (SICOT) (2015) 39:27–33
Table 1 Major complications
Complications
Total
Infection Dislocation Nonunion of osteotomy Sciatic nerve palsy Aseptic loosening
0 0 0 0 2
Intraoperative femoral fracture Deep venous thrombosis
0 0
Discussion Crowe type IV DDH presents a challenge for THA. In dealing with such cases, the surgeon should anticipate being faced with problems on both the acetabular and femoral sides. As regards the acetabulum, there are usually segmental defects that might be superior, anterior or posterior. The acetabulum is usually excessively anteverted, shallow and small, reflected by the small distance between the anterior and posterior walls, which presents a difficulty in reaching proper cup size with adequate bony coverage. On the femoral side, there is usually excessive anteversion, and the femoral canal is usually narrow, with pencil-like cortices. Another important issue in neglected dysplastic hips is soft-tissue contracture that results from the longstanding pathology. There is shortening of the neurovascular bundle, with general decrease in tissue excursion with subsequent difficulty in reducing the head in the true acetabulum and subsequent difficulty in restoring limb length without putting the sciatic nerve at risk of injury. In order to address these problems, femoral shortening osteotomy, with
its different types, was used to facilitate restoring hip centre and leg length without sciatic nerve compromise. The purpose of this study was to determine union rate, complications and HHS in a series of patients undergoing cementless THA and simultaneous subtrochanteric short oblique osteotomy for neglected DDH. Our union rate of 100 % is similar to reported results [20, 29, 31, 34] and compare favourably with other studies using THA with subtrochanteric osteotomy and cementless stem [4, 16, 18, 30, 32, 33, 35]. Total revision rate in our study was 14 % (two cases) for aseptic loosening, which compare favourably with revision rates in other studies [4, 16, 18, 20, 29, 31, 33, 34] and inferior to results reported by Sener et al. [30], Onodera et al. [32], and Nagoya et al. [35]. We had no complications of dislocation, infection, sciatic nerve palsy, intraoperative femoral fracture or deep vein thrombosis (Table 3). Absence of dislocation in this series can be explained by proper component orientation, restoring abductor lever arm by placing the cup in the true acetabulum and restoring the anatomical centre of hip rotation. In addition the subtrochanteric osteotomy allowed internal rotation of the proximal fragment, if needed, for stability during trial assessment. Using the posterior approach in this series may counteract the tendency towards anterior dislocation due to the excessive femoral anteversion found in neglected dysplastic hips. Osteotomy union occurred in all cases, and may be attributed to many factors: First, oblique osteotomy used in this study has two main advantages: (1) it provides rotational stability at the osteotomy site, and (2) it increases the surface area at the osteotomy site, which in turn increases the union rate. Also, the use of bone grafts at the osteotomy
Table 2 Demography, leg-length discrepancy (LLD), and Harris Hip Score (HHS) No.
Sex
Age
FU (years)
Preop LLD (cm)
Postop LLD (cm)
Preop HHS
HHS 6 months postop
HHS 12 months postop
1 2 3 4 5
F M F M F
29 27 38 45 27
3 2 4 5 8
4 6 7 0 5
0 1.5 2.5 0 1
57 33 24 33 54
89 73 62 83 87
92 81 68 87 90
6 7 8 9 10 11 12 13 14
F M F F M M F M F
46 54 39 39 37 28 30 49 36
7 4.5 6 6 4.5 4 3 4 5.5
3 6 – – 3 5 5 3 4
0 1.5 – – 0 1 1 0 0
56 29 33 35 53 31 35 57 59
83 68 68 81 86 73 76 88 89
86 81 83 87 90 87 88 92 90
FU follow-up, Preop pre-operative, Postop postoperative
2 (10 %) 5 (18 %) 0 0 0 0 0 0 0 0 4 (14 %) 0 2 (10 %) 4 (14 %) 1 (7 %) 2 (10 %) 7 (25 %) 2 (14 %) 19 (95 %) 26 (93 %) 14 (100 %) Cementless Cementless Cementless 8.1 (4–11.5) 4.8 (2–13.4) 4.75 (2–8) 20 28 14 Nagoya et al. 2009 [35] Krych et al. 2009 [18] Current study
55 (44–69) 48 (30–72) 37 (27–54)
5 (11 %) 0 2 (22 %) 0 0 6 (43 %) 4 (6 %) 3 (13 %) 0 NS 0 0 3 (11 %) 0 NS 5 (7 %) 0 0 1 (2 %) 0 0 2 (7 %) 0 0 0 0 0 2 (4 %) 0 1 (11 %) 0 3 (14 %) 1 (7 %) 3 (4 %) 1 (4 %) 4 (18 %) 3 (7 %) 0 1 (11 %) 2 (7 %) 2 (9 %) 1 (7 %) 5 (7 %) 3 (13 %) 0 8 (17 %) 1 (14 %) 2 (22 %) 2 (7 %) 5 (23 %) 1 (7 %) 29 (43 %) 4 (17 %) 4 (18 %) 44 (96 %) 7 (100 %) 9 (100 %) 26 (93 %) 22 (100 %) 13 (93 %) 58 (95 %) 21 (88 %) 23 (100 %) cementless cementless Cementless Cementless Cementless Cementless Cementless Cementless Cementless 3.2 (1–5.9) 2.7 (0.3–6) 4.7 (0.5–7.2) 4 (0.6–7.7) 2.1 (0.7–7.8) 5 (3–7.9) 12.3 (9–15) 4.7 (2–7.6) 8 (5–14) 46 7 9 28 22 14 61 24 23 Paavilainen et al. 1990 [16] Becker et al. 1995 [20] Bruce et al. 2000 [29] Sener et al. 2002 [30] Carlsson et al. 2003 [31] Onodera et al. 2006 [32] Eskelinen et al. 2006 [4] Park et al. 2007 [33] Bernasek et al. 2007 [34]
50 (22–78) 61 (48–72) 53 (26–77) 43 (26–64) 55 (23–80) 55 (44–69) 54 (29–74) 49 (20–66) 43 (17–67)
Femoral revisions (%) Total revisions (%) Union (%) Stem type Mean follow-up (years) No. patients
Mean age (years, range)
31
Author
Table 3 Overview of previous studies of total hip arthroplasty (THA) with subtrochanteric osteotomy using cementless femoral stem
Dislocations (%)
Deep infections (%)
Neurologic injuries (%)
Intraoperative femoral fracture (%)
International Orthopaedics (SICOT) (2015) 39:27–33
site, both morselised and structural, and absence of infection are other factors in promoting union. Finally, absence of any retained hardware from previous surgeries may be another factor improving the union rate, as retained metalwork has been proved to add specific difficulties in performing THA [41]. There was no sciatic nerve palsy, either transient or permanent, in our series. Femoral lengthening by >4 cm increases the incidence of nerve palsy, and various authors have recommended lengthening the femur by
