Simultaneous powering of forearm pronation and key pinch in tetraplegia using a single muscle-tendon unit

Fridén J, Reinholdt Gohritz A,Peace WJ, Ward SR, Lieber RL. J Hand Surg Eur 37(4):323-8, 2012.

This study clinically assessed the concept that both thumb flexion and forearm pronation can be restored by brachioradialis (BR)-to-flexor pollicis longus (FPL) tendon transfer if the BR is passed dorsal to the radius. Six patients [two women and four men, mean age 32.3 years (SD 4.9, range 23-56)] underwent BR-to-FPL transfer dorsal to the radius and through the interosseous membrane (IOM). Lateral key pinch strength and pronation range of motion (ROM) were measured 1 year after surgery. A group of six patients [two women and four men, mean age 31.2 years (SD 5.0, range 19-52)] who underwent traditional palmar BR-to-FPL was included for comparison. Postoperative active pronation was significantly greater in the dorsal transfer group compared to the palmar group [149 (SD 6) and 75 (SD 3), respectively] and pinch strength was similar in the two groups [1.28 (SD 0.16) kg and 1.20 (SD0.21) kg, respectively]. We conclude that it is feasible to reconstruct lateral key pinch and forearm pronation simultaneously using only the BR motor.

A Single-stage Operation for Reconstruction of Hand Flexion, Extension, and Intrinsic Function in Tetraplegia: The Alphabet Procedure

Fridén J, Reinholdt C, Turcsányii, Gohritz A. Tech Hand Up Extrem Surg 15:230-235, 2011.

Surgical reconstruction is an established method to restore grip and grasp function after traumatic cervical spinal cord injury and tetraplegia. It can offer the patient improved ability to perform activities of daily living. Traditionally, surgical reconstruction of hand function has required separate operations for flexors and extensors. Here, we present a combination of procedures that provides key pinch and finger flexion together with opening of hand as a 1-stage operation. This reconstruction includes 7 individual operations that are performed in the following order: (1) split flexor pollicis longus-extensor pollicis longus distal thumb tenodesis, (2) reconstruction of passive interossei, (3) thumb CMC arthrodesis (4) brachioradialis-flexor pollicis longus tendon transfer, (5) extensor carpi radialis longus-flexor digitorum profundus tendon transfer, (6) EPL tenodesis, and (7) extensor carpi ulnaris tenodesis. We have chosen to entitle this reconstruction the alphabet or ABCDEFG procedure, an abbreviation for Advanced Balanced Combined Digital Extensor Flexor Grip reconstruction. To reduce the risk of adhesions after this extensive surgery and to facilitate relearning the activation of transferred muscles with new functions, early active training is performed. It is concluded that this 1-stage combination of operations can reliably provide grip, grasp, and release function in persons with C6 tetraplegia, patient satisfaction is high, time and effort for patient and caregivers are less, and incidence of complications is comparable with other published treatment modalities.

Performance of prioritized activities is not correlated with functional factors after grip reconstruction in tetraplegia

Wangdell J, Fridén J. Rehabil Med 2011; 43: 626–630.

Objective: To investigate the correlation between perceived performance in prioritized activities and physical conditions related to grip reconstruction. Design: Retrospective clinical outcome study.
Patients: Forty-seven individuals with tetraplegia were included in the study. Each participant underwent tendon transfer surgery in the hand between November 2002 and April 2009 and had a complete 1-year follow-up.
Methods: Functional characteristics and performance data were collected from our database and medical records. Patients' perceived performances in prioritized activities were recorded using the Canadian Occupational Performance Measurement. Preoperative data included age at surgery, time since injury, severity of injury, sensibility and hand dominance. At 1-year follow-up, grip strength, key pinch strength, finger pulp-to-palm distance, distance between thumb and index finger and wrist flexion were measured. Correlation rank coefficient was used to test the possible relationship between physical data and activity performance.
Results: There were improvements in both functional factors and in rated performance of prioritized activities after surgery. There was no correlation between performance change and any of the physical functions, the factors known before surgery, or the functional outcome factors.
Conclusion: No correlation exists between a single functional outcome parameter and the patients' perceived performance of their prioritized goals in reconstructive hand surgery in tetraplegia.

Selective release of the digital extensor hood to reduce intrinsic tightness in tetraplegia

Reinholdt C, Fridén J. J Plast Surg Hand Surg. 2011 Apr;45(2):83-9.

Patients with tetraplegia may have various degrees of spasticity in the hand ranging from a completely clenched fist to reduced control of grip at triggered spasticity. The objective of the present study was to evaluate the functional effect of the distal ulnar intrinsic release procedure to reduce intrinsic tightness. Seventeen patients with tetraplegia (37 fingers) and with prominent intrinsic tightness were operated on for distal intrinsic release with a modification of the procedure to include only the ulnar side of the proximal phalanx. All the patients had more pronounced tightness on the ulnar than on the radial side of the affected finger. Long fingers were consistently the most affected digits. The intrinsic tightness was released completely in all patients and the range of motion (ROM) was improved by 25%, and up to 45% in mild and severe cases, respectively. The good immediate effects of treatment as shown by increased ROM remained intact by 6 months postoperatively. These data suggest that the distal ulnar intrinsic release procedure is a simple and valuable way of reducing intrinsic tightness and improving hand function and grip for patients with intrinsic tightness. This procedure can be added to other procedures such as lengthening and transfer of tendons.

Muscle biopsies from the supraspinatus in retracted rotator cuff tears respond normally to passive mechanical testing: a pilot study

Einarssson F, Runesson E, Karlsson J, Fridén J. Knee Surg Sports Traumatol Arthrosc. 2011 Mar;19(3):503-7.

PURPOSE: The aim of the present study was to assess the function of the isolated muscle component in retracted rotator cuff tears.

METHODS: Muscle biopsies were harvested from the supraspinatus and the ipsilateral deltoid in seven patients undergoing surgery for a large, retracted rotator cuff tear. Single fibres and fibre bundles were subjected to passive stretching in vitro with subsequent recordings of tension and sarcomere lengths using the laser diffraction technique. Stress-strain curves were plotted, and the elastic modulus was calculated for all preparations. Morphology was evaluated with regard to collagen fraction, ratio between fast and slow fibres, fibre size and fibre size variability using standard staining techniques.

RESULTS: Intra-individual comparisons of the stress-strain curves showed a high degree of conformity in terms of both shape and tangent values, and there were no statistically significant differences in the elastic modulus for single fibres and bundles in the deltoid and supraspinatus muscles, respectively, supported by the analysis of the observed confidence interval of the differences between the paired values of the elastic modulus. There were no differences in collagen content, fibre size and ratio between fast and slow fibres in the deltoid and supraspinatus muscles, respectively.

CONCLUSION: We conclude that muscle biopsies from the supraspinatus in retracted rotator cuff tears respond normally to mechanical testing in vitro.

Shortened rehabilitation period using a modified surgical technique for reconstruction of lost elbow extension in tetraplegia

Turcsanyi I, Fridén J. J Plast Surg Hand Surg 44(3):156-62, 2010.

Our aim was to evaluate the functional outcome of reconstruction of elbow extension in tetraplegia using a new technique for improving the attachment sites of posterior deltoid-to-triceps transfer in conjunction with an active rehabilitation programme. Ten tetraplegic patients (15 arms) had modified deltoid-to-triceps transfer using a tibialis anterior tendon graft. The operation included large overlaps between the tendon attachments, and additional security by anchoring the distal stump of the tendon graft to the olecranon. During the first 3 weeks of immobilisation, isometric contractions were made and during the following 4 weeks the flexion angle of the elbow was increased by 15 degrees a week; weights were also used to reinforce muscle strength. The mean follow up was 10 months (range 5-19). The elbow extension strength after posterior deltoid-to-triceps transfer was measured in horizontal and vertical planes. After rehabilitation the active range of motion and strength of elbow extension had improved substantially. The mean active elbow extension range of motion was 132 degrees (range 120 degrees -145 degrees ) and the elbow could be extended actively in all planes. Elbow extension strength was restored to well above the counteraction of the weight of the arm. Mean (SEM) elbow extension was significantly greater in the horizontal shoulder plane compared with the vertical plane (10.4 (1.0) compared with 6.5 (1.2) Nm, p < 0.001) and strength increased roughly linearly as the degree of flexion of the elbow increased. The most dramatic increase was in the range between 120 degrees and 135 degrees of flexion, regardless of the plane of action of the shoulder. We have shown good functional results and a shorter rehabilitation period using a rigorous suturing technique that allows for active strength and mobility training without additional adverse effects.

Mechanical Feasibility of Immediate Mobilization of the Brachioradialis Muscle After Tendon Transfer.

Fridén J, Shillito MC, Chehab EF, Finneran JJ, Ward SR, Lieber RL. J Hand Surg Am 35:1473-1478, 2010

PURPOSE: Tendon transfer is often used to restore key pinch after cervical spinal cord injury. Current postoperative recommendations include elbow immobilization in a flexed position to protect the brachioradialis-flexor pollicis longus (BR-FPL) repair. The purpose of this study was to measure the BR-FPL tendon tension across a range of wrist and elbow joint angles to determine whether joint motion could cause repair rupture.

METHODS: We performed BR-to-FPL tendon transfers on fresh-frozen cadaveric arms (n = 8) and instrumented the BR-FPL tendon with a buckle transducer. Arms were ranged at 4 wrist angles from 45 degrees of flexion to 45 degrees of extension and 8 elbow angles from 90 degrees of flexion to full extension, measuring tension across the BR-FPL repair at each angle. Subsequently, the BR-FPL tendon constructs were removed and elongated to failure.

RESULTS: Over a wide wrist and elbow range of motion, BR-FPL tendon tension was under 20 N. Two-way analysis of variance with repeated measures revealed a significant effect of wrist joint angle (p<.001) and elbow joint angle (p<.001) with significant interaction between elbow and joint angles (p<.001). Because the failure load of the repair site was 203 +/- 19 N, over 10 times the loads that would be expected to occur at the repair site, our results demonstrate that the repair has a safety factor of at least 10.