Partially Lacerated Digital Flexor Tendons: A Cadaveric Study Determining the Intact Cross-sectional Area and Biomechanical Analysis.

BACKGROUND: The extent of injury in partially lacerated tendons has conventionally been expressed as a percentage of the total tendon, to justify surgical repair. We propose a more objective method to estimate the cross-sectional area of the remnant intact tendon and to determine if the remaining tendon fibers can withstand the tensile forces of early active mobilization against resistance. METHODS: The study was done on 20 cadaveric specimens, which were randomly assigned to receive a laceration of 25%, 50%, or 75% of the measured transverse tendon diameter. The circumference of the remaining intact portion of the partially lacerated tendon was measured and converted using a formula to determine the derived cross-sectional area (D-CSA). These D-CSA values were then validated by comparing them to digitally measured cross-sectional areas using a computer software program (computer-measured cross-sectional area, C-CSA). In addition, the ultimate tensile strength (UTS) of these partially lacerated tendons was analyzed to determine if a threshold exists beyond which surgical repair of a partially lacerated tendon is indicated. RESULTS: We found that the D-CSAs matched moderately with C-CSAs, with 0.622 of Pearson correlation coefficient. The UTSs of tendons with CSAs above 8 mm in circumference were consistently above 150 N. CONCLUSION: Measurement of the circumference of the partially lacerated tendon to obtain the D-CSA could be an accurate and practical method to benchmark residual tendon strength in the management of partially lacerated tendons.

The impact of various simulated arthrodesis angles of the proximal interphalangeal joint of the ring and middle finger on grip strength.

INTRODUCTION: Arthrodesis of the proximal interphalangeal (PIP) joint at 40° angle has been proposed by many authors. A smaller angle of arthrodesis results in weaker grip strength of the hand from the quadriga effect. However, arthrodesis at 40° compromises other aspects of hand function including poor aesthetic appearance. This paper aims to quantify the decrease in grip strength at 40°, 20°, and 0° of arthrodesis. MATERIALS AND METHODS: Grip strengths of the hand were measured using a BASELINE dynamometer at settings II, III, and IV. Baseline grip strength of the subjects were first measured without wearing a splint. Thereafter, subjects wore thermoplastic splints to simulate arthrodesis of the middle and ring finger PIP joint at 40°, 20°, and 0°, and grip strengths were measured again. The grip strength of the hand with simulated arthrodesis was then calculated as a ratio of the baseline. RESULTS: There were 50 subjects yielding 100 sets of results. The results show that average grip strength ratio of the hand decreases progressively from 40° and 20° and to 0° of arthrodesis for both the middle and ring finger. However, the difference in grip strength ratio between 40° and 20° of arthrodesis was minimal. Simulated arthrodesis of the middle finger affected the grip strength ratio more than arthrodesis of the ring finger, and compromised gripping of a smaller handle more than a wider one. CONCLUSION: The decrease in grip strength from 40° to 20° simulated fusion of PIP joint was minimal. Therefore, in so far as grip strength loss is concerned, arthrodesis of the PIP joint at an angle less than 40° can be considered for patients with individual functional and aesthetic concerns.

Shoulder abduction reconstruction for C5-7 avulsion brachial plexus injury by dual nerve transfers: spinal accessory to suprascapular nerve and partial median or ulnar to axillary nerve.

Results of shoulder abduction reconstruction in partial upper-type brachial plexus avulsion injuries are better when a triceps nerve is transferred to the axillary nerve in addition to the spinal accessory to suprascapular nerve transfer. However, in C5-7 avulsion injuries, the triceps nerve may be unavailable as a donor nerve. We report the results of an alternative neurotization to the axillary nerve using either a partial median or ulnar nerve. Patients with C5, 6 ± 7 avulsion injuries and weak triceps who underwent dual nerve transfers for shoulder abduction reconstruction were recruited for the study. The second neurotization to the axillary nerve was from either a partial median or ulnar nerve that had an expandable muscle innervation of ≥ M4 motor power. Patients were assessed for recovery of shoulder abduction and external rotation. Nine patients (median age = 23 years) underwent these dual neurotizations from March 2005 to April 2013. The median time to surgery was 4.5 months. Recovery of shoulder abduction averaged 114.4° (range 90°-180°) and external rotation averaged 136.3° (range 135°-140°). Final shoulder abduction power was > M3 in all 9 patients and ≥ M4 in 6 patients. One patient with partial median nerve transfer had transient hypoaesthesia in his thumb and index finger and another had a residual M4 power in his thumb and index finger flexors. In C5-7 avulsion injuries, dual nerve transfers of the spinal accessory to suprascapular nerve and partial median or ulnar nerve to axillary nerve are good options for shoulder abduction reconstruction with minimal morbidity. Level of evidence is level IV.

Elbow Flexion Reconstruction in Brachial Plexus Avulsion Injuries - Results with Intercostal Nerve and Distal Nerve Transfers.

Background: The neural surgical options for reconstruction of elbow flexion in brachial plexus injuries depend on the availability of nerve donors. In upper-type avulsion injuries, the ulnar or median nerves, when intact, are reliable intra-plexal donor nerves for transfers to the biceps muscle. In complete avulsion injuries, donors are limited to extra-plexal sources, such as intercostal nerves (ICNs). Methods: We reviewed our results of ICN and partial distal nerve (ulnar or median) transfers for elbow flexion reconstruction in patients with brachial plexus avulsion injuries. The time taken for recovery of elbow flexion strength to M3 and the final motor outcome at 2 years were compared between both groups. Results: 38 patients were included in this study. 27 had ICN transfers to the musculocutaneous nerve (MCN), 8 had partial ulnar nerve transfers and 3 had partial median nerve transfers to the MCN's biceps motor branch. The mean time interval from injury to surgery was 3.6 months. Recovery of elbow flexion was observed earlier in the distal nerve transfer group (p < 0.05). Overall, success rates were higher in patients with distal nerve transfers (100%), compared to ICN transfers (63%) at 2 years (p = 0.018). Patients with distal nerve transfers achieved a higher final median strength of M4.0 [Interquartile range (IQR) 3.5-4.5], compared to M3.5 (IQR 2.0-4.0) in the ICN group (p = 0.031). In the subgroup of patients with upper-type brachial plexus injuries, there were no significant differences in motor outcomes between the ICN versus distal nerve transfers group. Conclusions: In our entire cohort, patients with distal nerve transfers had faster motor recovery and better elbow flexion power than patients with ICN transfers. In patients with partial brachial plexus injuries, outcomes of ICN transfers were not inferior to distal nerve transfers.

Trigonometry-Integrated 'Lift' Technique (TILT) for Restoring Volar Tilt in Distal Radius Fractures: Description of Technique and Preliminary Results.

BACKGROUND: Restoration of extra-articular and intra-articular parameters are important considerations during operative fixation of distal radius fractures. Restoration of volar tilt by using visual estimation and the 'lift' technique has previously been described. The aim of our study was to describe a mathematical technique for accurately restoring the volar tilt of the distal radius to acceptable anatomic values. METHODS: A retrospective review of cases performed using the trigonometry-integrated ' lift' technique (TILT) was performed. This technique uses the pre-operative volar tilt angle as well as the dimensions of the implant to calculate the 'lift' required to restore volar tilt. Intra-operative angles were measured using a marked transparency overlay on fluoroscopic images. Pre-operative and post-operative volar tilt were measured and analysed. RESULTS: Twenty-seven fractures were included in the study, with 20 being classified as Arbeitsgemeinschaft für Osteosynthesefragen (AO) C-type. Pre-'lift' volar tilt ranged from 0° to -20°. Post-'lift' volar tilt ranged from 2° to 16°, with all but three cases ranging from 5° to 15°. The mean volar tilt achieved was 10.2°. CONCLUSIONS: The trigonometry-integrated 'lift' technique resulted in reliable intra-operative restoration of anatomic volar tilt in distal radius fractures.

Epidemiology and management of surgical upper limb infections in patients with end-stage renal failure.

INTRODUCTION: Hand infections in patients with end-stage renal failure (ESRF) are more diffi cult to treat and have had the worse outcomes. This paper examines the epidemiology, bacteriology and outcomes of surgically managed upper limb infections in these vulnerable patients. MATERIALS AND METHODS: All patients from a single centre with surgically-managed upper limb infections between 2001 and 2007 were reviewed. We collected epidemiological data on demographics, type and site of infection, bacteriology, surgical treatment, complications and mortality. RESULTS: Forty-seven out of 803 (6%) patients with surgically managed upper limb infections in the study period had ESRF. The average age was 59 years. ESRF was secondary to diabetes in 88% of cases. Patients presented on average 7 days after onset of symptoms. Abscesses (34%), wet gangrene (26%) and osteomyelitis (11%) were the commonest infections. Methicillin-resistant Staphylococcus aureus (MRSA) was the commonest pathogen (29%), occurring either in isolation or with other organisms. Eighteen percent of single organisms cultured were gram-negative. Multiple organisms occurred in 29%. A median of 2 operations were required. Thirty-six percent of all cases required amputation. Twenty-fi ve percent of patients had a life-threatening event (myocardial infarction or septic shock) during treatment. CONCLUSIONS: ESRF patients present late with severe upper limb infections. Nosocomial infections are common. Initial empirical antibiotic treatment should cover MRSA and gram-negative bacteria. Immediate referral to a hand surgery unit is recommended. Multi-disciplinary management of the patient with input from physicians and anaesthetists or intensivists in the perioperative period is necessary to optimise the patient for surgery and to manage active medical comorbidities and complications after surgery.

Free digital artery flap: an ideal flap for large finger defects in situations where local flaps are precluded.

The heterodigital arterialized flap is increasingly accepted as a flap of choice for reconstruction of large finger wounds. However, in situations where the adjacent fingers sustained concomitant injuries, the use of this flap as a local flap is precluded. This paper describes our experience with the free digital artery flap as an evolution of the heterodigital arterialized flap. Four patients with large finger wounds were reconstructed with free digital artery flap. Our indications for digital artery free flap were concomitant injuries to adjacent fingers that precluded their use as donor sites. The arterial supply of the flap was from the digital artery and the venous drainage was from the dominant dorsal vein of the finger. The flap was harvested from the ulnar side of the finger. The digital nerve was left in situ to minimize donor morbidity. The donor site was covered with a full-thickness skin graft and secured with bolster dressings. Early intensive mobilization was implemented for all patients. All flaps survived. No venous congestion was noted and primary healing was achieved in all flaps. In addition to providing well-vascularized tissue for coverage of vital structures, the digital artery was also used as a flow-through flap for finger revascularization in one patient. Donor-site morbidity was minimal, with all fingers retaining protective pulp sensation and the distal and proximal interphalangeal joints retaining full ranges of motion. In conclusion, the free digital artery flap is a versatile flap that is ideal for coverage of large-sized finger defects in situations where local flaps are unavailable. Donor-site morbidity can be minimized by preservation of the digital nerve, firmly securing the skin graft with bolster dressings, and early mobilization of the donor finger.

Mycobacterium marinum as a cause of chronic granulomatous tenosynovitis in the hand.

OBJECTIVE: Mycobacterium marinum is an uncommon cause of chronic granulomatous flexor tenosynovitis and leads to significant morbidity in the hand. This paper aims to review our treatment of this infection and its clinical outcomes. METHODS: We treated five cases of M. marinum flexor tenosynovitis from 2001 to 2006, which were confirmed after 6 weeks of mycobacterial culture. RESULTS: All the patients were healthy immuno-competent hosts. There was a history of injury by a marine animal in each patient. Presentation was delayed at an average of 32.0 days after the injury. Excisional debridement was performed at an average of 63.4 days after the injury. The average number of debridements performed was 3.4. One patient had to undergo ray amputation to control the infection. The average duration of oral antibiotics was 15.4 weeks. Post-operatively, there were reductions in total active motion in all patients. CONCLUSION: A high index of suspicion, based on the history and intra-operative findings, is necessary when managing these patients. This infection runs a protracted course that requires multiple debridements and is associated with poor functional outcome.

Necrotising fasciitis and traditional medical therapy-- a dangerous liaison.

INTRODUCTION: Necrotising fasciitis is a disease associated with high morbidity and mortality, and multi-focal necrotising fasciitis is uncommon. We present 2 cases of concurrent necrotising fasciitis of contralateral upper and lower limbs. CLINICAL PICTURE: Both presented with pain, swelling, bruising or necrosis of the affected extremities. Traditional medical therapy was sought prior to their presentation. TREATMENT: After initial debridement, one patient subsequently underwent amputation of the contralateral forearm and leg. The other underwent a forearm amputation, but refused a below-knee amputation. OUTCOME: The first patient survived, while the second died. CONCLUSION: Traditional medical therapy can cause bacterial inoculation, leading to necrotising fasciitis, and also leads to delay in appropriate treatment. Radical surgery is needed to optimise patient survival.

Extending the reach of the heterodigital arterialized flap by vein division and repair.

The heterodigital arterialized flap is ideal for nonsensory reconstruction of sizable soft-tissue defects in the proximal fingers, web spaces, and the hand. The inclusion of a dorsal vein augments the venous drainage of this digital island flap and avoids the problem of postoperative venous congestion, which is a common problem in digital island flaps. However, the presence of a dorsal vein pedicle inhibits flap mobility somewhat, and the reach of the flap is mainly limited to adjacent fingers. In situations that demand a transfer from a nonadjacent donor finger or when the reach from the adjacent donor finger is inadequate, the dorsal vein pedicle can be temporarily divided and then anastomosed microsurgically after flap transfer is performed. This enables the reach of the flap to be extended up to two fingers from the donor finger. The authors performed this "partially free" heterodigital arterialized flap in 11 consecutive patients between 1991 and 2001. The average size of the defects was 4.4 x 2.3 cm. All of the flaps survived completely, without any evidence of postoperative flap congestion. Healing of all of the flaps was primary and did not result in any scarring. All of the donor fingers had "normal" two-point discrimination of 3 to 5 mm. All of the donor fingers retained excellent or good total active motion, as graded by the criteria of Strickland and Glogovac.