September 23, 2014
4:16:09pm
WSPC/135-HS
FA1
1472032
Hand Surgery, Vol. 19, No. 3 (2014) 437–439 © World Scientific Publishing Company DOI: 10.1142/S0218810414720320
LOCKING FINGER DUE TO A PARTIAL LACERATION OF THE FLEXOR DIGITORUM SUPERFICIALIS TENDON: A CASE REPORT
Hand Surg. 2014.19:437-439. Downloaded from www.worldscientific.com by CHINESE UNIVERSITY OF HONG KONG on 02/11/15. For personal use only.
Yasuhiro Seki and Hiroshi Kuroda Department of Orthopaedic Surgery, Kameda Medical Centre Chiba 296-8602, Japan Received 11 February 2014; Revised 29 May 2014; Accepted 2 June 2014; Published 12 August 2014 ABSTRACT A 39-year-old woman sustained a small wound on the palm of her right hand, which quickly healed naturally; however, a month later pain and limited range of motion were noted in her right finger. Surgery revealed the radial half of the flexor digitorum superficialis (FDS) tendon was ruptured and formed a flap, which hooked at the entrance of the A1 pulley. The proximal stump was sutured to the remaining ulnar (normal) side of the FDS tendon. Locking occurs between the tendon flap and the tendon sheath; therefore, when there is no fibrous tendon sheath near the partially ruptured tendon, locking will not occur. Keywords: Trigger Finger; Tendon Flap; Tendon Adhesion.
INTRODUCTION
on the palm of the fourth metacarpophalangeal joint (on the A1 pulley) was present. The patient could not extend the proximal interphalangeal (PIP) joint of the ring finger by more than 90 degrees, either actively or passively (Fig. 1), while flexion was possible. Surgery performed via the volar approach revealed a thin, scarred A1 pulley. After the pulley was opened, partial tear of the flexor digitorum superficialis (FDS) tendon was disclosed. The radial half of the FDS tendon was ruptured and formed a flap at the proximal stump (Fig. 2). The stump hooked at the entrance of the A1 pulley. On the other hand, the distal stump adhered to the ulnar (normal) side of the FDS tendon, meaning no flap formation. This distal one, therefore, did not disturb tendon sliding. The flexor digitorum profundus tendon was intact. We trimmed the proximal stump and sutured it to the ulnar (normal) side of the FDS tendon (Fig. 3), because it
Partial flexor tendon laceration is common. Some authors have reported trigger finger due to laceration; however, locking of the finger by laceration has never been reported. We present a case of a locking finger due to partial laceration of the flexor digitorum superficialis tendon.
CASE REPORT A 39-year-old woman fell, holding a glass in her right hand. She sustained a small wound on her palm, which quickly healed naturally. However, pain and limited range of motion of the right ring finger developed several days later. Her symptoms gradually worsened. A month after the injury, she presented to a nearby clinic. Because steroid injection was not effective, she was referred to our hospital. A small, well-healed scar (5 mm)
Correspondence to: Dr. Yasuhiro Seki, Department of Orthopaedic Surgery, Kameda Medical Centre, 929 Higashi-cho, Kamogawa-city, Chiba 296-8602, Japan. Email: [email protected] 437
September 23, 2014
Hand Surg. 2014.19:437-439. Downloaded from www.worldscientific.com by CHINESE UNIVERSITY OF HONG KONG on 02/11/15. For personal use only.
438
4:16:09pm
WSPC/135-HS
FA1
1472032
Y. Seki & H. Kuroda
Fig. 1 It is impossible to extend the proximal interphalangeal joint of the ring finger.
Fig. 3 The proximal stump of the flexor digitorum superficialis (FDS) tendon sutured to the ulnar FDS tendon.
DISCUSSION
Fig. 2 Partial laceration (radial half) of the flexor digitorum superficialis tendon. The proximal stump (white arrow) shows a flap formation, while the distal one (black arrow) adheres to the remaining normal (ulnar) tendon.
was difficult to suture end to end. Then, nearly the entire A1 pulley was resected, full and smooth range of motion was confirmed, and a splint was applied in the extension position. One week after the surgery, motion exercises of the finger were begun. The finger function recovered fully.
A few authors have reported1–3 trigger finger due to partial flexor tendon laceration; however, locking of the finger by tendon laceration has never been reported. To examine and diagnose the partial laceration, ultrasonography1 and magnetic resonance imaging2 were performed. One study reported4 that the cause of triggering is not the bulbous scar formation at the site of the partial tendon laceration, but the bunching of the tendon fibres distal or proximal to the laceration site. Additionally, the authors reported that flap formation could result from failure of incorporation of the bunched part of the tendon into the healing process after a laceration. In the current case, range of motion became progressively limited after the initial injury. We thought that during this period the stump gradually formed a flap, resulting in locking. The torn tendon was found to be 50% of the tendon width. This caused weakness of the connection between the torn tendon (radial half) and the remaining intact tendon (ulnar half), because the FDS tendon tends to separate into radial and ulnar portions toward the chiasma where insertion into the middle phalanx occurs. As a result, the torn tendon easily separates from the remaining tendon, forming the longer flap. Moreover, the injured zone is also important in causing the finger to lock. Locking occurs between the tendon flap and the
September 23, 2014
4:16:10pm
WSPC/135-HS
FA1
1472032
Hand Surg. 2014.19:437-439. Downloaded from www.worldscientific.com by CHINESE UNIVERSITY OF HONG KONG on 02/11/15. For personal use only.
Locking Finger due to a Partial Laceration of the Flexor Digitorum Superficialis Tendon
tendon sheath because the proximal portion of the torn tendon becomes stuck against the tendon sheath preventing extension of the finger. Therefore, even if the partial laceration is 50% of the tendon width, locking will not occur when there is no fibrous tendon sheath. In our patient, the tendon laceration was not repairable; therefore, it was trimmed and sutured to the remaining normal tendon. A few articles1,2 on trigger finger have described cases where the laceration was only excised, while a different article4 reported that they had repaired the laceration in order to avoid complete rupture. We, however, did neither, as it was difficult to suture end to end because the gap was wide. We thought that simple excision of the laceration might cause recurrence of a flap formation at the new stump. Hence, we sutured the
439
stump to the remaining normal tendon. This approach is still questionable.
References 1. Fujiwara M, A case of trigger finger following partial laceration of flexor digitorum superficialis and review of the literature, Arch Orthop Trauma Surg 125:430–432, 2005. 2. Okano T, Hidaka N, Nakamura H, Partial laceration of the flexor tendon as an unusual cause of trigger finger, J Plast Surg Hand Surg 45:248– 251, 2011. 3. Tohyama M, Tsujio T, Yanagida I, Trigger finger caused by an old partial flexor tendon laceration: a case report, Hand Surg 10:105–108, 2005. 4. al-Qattan MM, Posnick JC, Lin KY, Triggering after partial tendon laceration, J Hand Surg Br 18:241–246, 1993.
4:16:09pm
WSPC/135-HS
FA1
1472032
Hand Surgery, Vol. 19, No. 3 (2014) 437–439 © World Scientific Publishing Company DOI: 10.1142/S0218810414720320
LOCKING FINGER DUE TO A PARTIAL LACERATION OF THE FLEXOR DIGITORUM SUPERFICIALIS TENDON: A CASE REPORT
Hand Surg. 2014.19:437-439. Downloaded from www.worldscientific.com by CHINESE UNIVERSITY OF HONG KONG on 02/11/15. For personal use only.
Yasuhiro Seki and Hiroshi Kuroda Department of Orthopaedic Surgery, Kameda Medical Centre Chiba 296-8602, Japan Received 11 February 2014; Revised 29 May 2014; Accepted 2 June 2014; Published 12 August 2014 ABSTRACT A 39-year-old woman sustained a small wound on the palm of her right hand, which quickly healed naturally; however, a month later pain and limited range of motion were noted in her right finger. Surgery revealed the radial half of the flexor digitorum superficialis (FDS) tendon was ruptured and formed a flap, which hooked at the entrance of the A1 pulley. The proximal stump was sutured to the remaining ulnar (normal) side of the FDS tendon. Locking occurs between the tendon flap and the tendon sheath; therefore, when there is no fibrous tendon sheath near the partially ruptured tendon, locking will not occur. Keywords: Trigger Finger; Tendon Flap; Tendon Adhesion.
INTRODUCTION
on the palm of the fourth metacarpophalangeal joint (on the A1 pulley) was present. The patient could not extend the proximal interphalangeal (PIP) joint of the ring finger by more than 90 degrees, either actively or passively (Fig. 1), while flexion was possible. Surgery performed via the volar approach revealed a thin, scarred A1 pulley. After the pulley was opened, partial tear of the flexor digitorum superficialis (FDS) tendon was disclosed. The radial half of the FDS tendon was ruptured and formed a flap at the proximal stump (Fig. 2). The stump hooked at the entrance of the A1 pulley. On the other hand, the distal stump adhered to the ulnar (normal) side of the FDS tendon, meaning no flap formation. This distal one, therefore, did not disturb tendon sliding. The flexor digitorum profundus tendon was intact. We trimmed the proximal stump and sutured it to the ulnar (normal) side of the FDS tendon (Fig. 3), because it
Partial flexor tendon laceration is common. Some authors have reported trigger finger due to laceration; however, locking of the finger by laceration has never been reported. We present a case of a locking finger due to partial laceration of the flexor digitorum superficialis tendon.
CASE REPORT A 39-year-old woman fell, holding a glass in her right hand. She sustained a small wound on her palm, which quickly healed naturally. However, pain and limited range of motion of the right ring finger developed several days later. Her symptoms gradually worsened. A month after the injury, she presented to a nearby clinic. Because steroid injection was not effective, she was referred to our hospital. A small, well-healed scar (5 mm)
Correspondence to: Dr. Yasuhiro Seki, Department of Orthopaedic Surgery, Kameda Medical Centre, 929 Higashi-cho, Kamogawa-city, Chiba 296-8602, Japan. Email: [email protected] 437
September 23, 2014
Hand Surg. 2014.19:437-439. Downloaded from www.worldscientific.com by CHINESE UNIVERSITY OF HONG KONG on 02/11/15. For personal use only.
438
4:16:09pm
WSPC/135-HS
FA1
1472032
Y. Seki & H. Kuroda
Fig. 1 It is impossible to extend the proximal interphalangeal joint of the ring finger.
Fig. 3 The proximal stump of the flexor digitorum superficialis (FDS) tendon sutured to the ulnar FDS tendon.
DISCUSSION
Fig. 2 Partial laceration (radial half) of the flexor digitorum superficialis tendon. The proximal stump (white arrow) shows a flap formation, while the distal one (black arrow) adheres to the remaining normal (ulnar) tendon.
was difficult to suture end to end. Then, nearly the entire A1 pulley was resected, full and smooth range of motion was confirmed, and a splint was applied in the extension position. One week after the surgery, motion exercises of the finger were begun. The finger function recovered fully.
A few authors have reported1–3 trigger finger due to partial flexor tendon laceration; however, locking of the finger by tendon laceration has never been reported. To examine and diagnose the partial laceration, ultrasonography1 and magnetic resonance imaging2 were performed. One study reported4 that the cause of triggering is not the bulbous scar formation at the site of the partial tendon laceration, but the bunching of the tendon fibres distal or proximal to the laceration site. Additionally, the authors reported that flap formation could result from failure of incorporation of the bunched part of the tendon into the healing process after a laceration. In the current case, range of motion became progressively limited after the initial injury. We thought that during this period the stump gradually formed a flap, resulting in locking. The torn tendon was found to be 50% of the tendon width. This caused weakness of the connection between the torn tendon (radial half) and the remaining intact tendon (ulnar half), because the FDS tendon tends to separate into radial and ulnar portions toward the chiasma where insertion into the middle phalanx occurs. As a result, the torn tendon easily separates from the remaining tendon, forming the longer flap. Moreover, the injured zone is also important in causing the finger to lock. Locking occurs between the tendon flap and the
September 23, 2014
4:16:10pm
WSPC/135-HS
FA1
1472032
Hand Surg. 2014.19:437-439. Downloaded from www.worldscientific.com by CHINESE UNIVERSITY OF HONG KONG on 02/11/15. For personal use only.
Locking Finger due to a Partial Laceration of the Flexor Digitorum Superficialis Tendon
tendon sheath because the proximal portion of the torn tendon becomes stuck against the tendon sheath preventing extension of the finger. Therefore, even if the partial laceration is 50% of the tendon width, locking will not occur when there is no fibrous tendon sheath. In our patient, the tendon laceration was not repairable; therefore, it was trimmed and sutured to the remaining normal tendon. A few articles1,2 on trigger finger have described cases where the laceration was only excised, while a different article4 reported that they had repaired the laceration in order to avoid complete rupture. We, however, did neither, as it was difficult to suture end to end because the gap was wide. We thought that simple excision of the laceration might cause recurrence of a flap formation at the new stump. Hence, we sutured the
439
stump to the remaining normal tendon. This approach is still questionable.
References 1. Fujiwara M, A case of trigger finger following partial laceration of flexor digitorum superficialis and review of the literature, Arch Orthop Trauma Surg 125:430–432, 2005. 2. Okano T, Hidaka N, Nakamura H, Partial laceration of the flexor tendon as an unusual cause of trigger finger, J Plast Surg Hand Surg 45:248– 251, 2011. 3. Tohyama M, Tsujio T, Yanagida I, Trigger finger caused by an old partial flexor tendon laceration: a case report, Hand Surg 10:105–108, 2005. 4. al-Qattan MM, Posnick JC, Lin KY, Triggering after partial tendon laceration, J Hand Surg Br 18:241–246, 1993.
