Kenneth R. Means

Clinical Outcomes of Zone II Flexor Tendon Repair Depending on Mechanism of Injury

PURPOSE To determine whether mechanism of injury affects outcomes of Zone II flexor tendon repairs. METHODS We retrospectively analyzed patients who underwent Zone II flexor tendon repair between 2001 and 2010 with a minimum of 12-month follow-up. Exclusion criteria included fingers with fracture, pulley reconstruction, or flexor tendon bowstringing. The saw group injuries were from saws or from tearing mechanisms; the sharp group had clean transection injuries from knives or glass. At final evaluation, primary outcomes were total passive motion (TPM) and total active motion (TAM) at the proximal interphalangeal and distal interphalangeal joints. Secondary comparisons included strength, Disabilities of the Shoulder, Arm, and Hand (DASH) score, percentage of postoperative tendon rupture, and percentage of patients requiring secondary surgery. The saw group had 13 patients with 17 fingers studied. The sharp group had 21 patients with 24 fingers studied. All patients had primary flexor digitorum profundus repairs in Zone II. Operative records review confirmed for all but 1 patient that flexor digitorum profundus injuries were repaired with a minimum of a 4-strand core suture technique. In the saw group, 9 of 14 fingers with a 50% or greater laceration of flexor digitorum superficialis were repaired; in the sharp group, 15 of 18 such flexor digitorum superficialis injuries were repaired. Average follow-up was 4 years (range, 1-9 y). RESULTS The saw group had significantly less TAM and TPM compared with the sharp group. There was no significant difference in DASH scores, strength measurements, or tendon rupture rates. The rate of secondary surgery was significantly higher in the saw group. CONCLUSIONS Tearing types of injury, such as those caused by saws, led to poorer outcomes for Zone II flexor tendon injuries compared with sharp injuries at an average follow-up of 4 years. Our results can be useful when discussing expected outcomes. Mechanism of injury in Zone II flexor tendon lacerations may eventually help define optimal treatment.

Stability of Fixation of Proximal Phalanx Unicondylar Fractures of the Hand: A Biomechanical Cadaver Study

PURPOSE To determine the relative stability of various fixation methods for proximal phalanx intra-articular unicondylar fractures during simulated early active motion. METHODS We created proximal phalangeal intra-articular unicondylar fractures in 13 fresh-frozen human cadaveric hands. Using a saw through a dorsal approach, we made an osteotomy beginning in the intercondylar notch and extending proximally at a 45° angle to the radial border of the proximal phalanx. We fixed each of the 4 fingers on each hand with a 1.5-mm headless compression screw, a 1.5-mm lag screw, two 1.1-mm smooth K-wires, or one 1.1-mm smooth K-wire. We rotated the order of constructs randomly for each hand. We simulated active range of motion on a custom-loading device at 0.25 Hz from full finger extension to full flexion for 2,000 cycles and measured displacement by a differential variable reluctance transducer. RESULTS We found no significant differences in displacement of the fracture site among the 4 methods of fixation. Movement in the control specimen with no osteotomy fixation was significantly higher than with each of the other fixation methods. CONCLUSIONS Biomechanical stability did not differ among the fixation methods for proximal phalanx unicondylar fractures in a flexion-extension active range of motion model. CLINICAL RELEVANCE Fixation of these fractures with any of the methods tested may provide sufficient stability to withstand postoperative therapy when there is no substantial resistance to active motion.

Palmaris Profundus Tendon Prohibiting Endoscopic Carpal Tunnel Release: Case Report

Palmaris profundus is an aberrant muscle of forearm and wrist anatomy. It has no discernible function, but its tendon has been implicated as a cause of carpal tunnel syndrome. Previously, all cases of palmaris profundus in the literature have been encountered during either open surgery or cadaveric dissection. We report a case of palmaris profundus encountered during attempted single-portal endoscopic carpal tunnel release, necessitating conversion to an open approach. There was a unique point of tendon insertion onto the undersurface of the transverse carpal ligament, more proximal than what has been previously described in the literature. There were other anomalies present as well, including a persistent median artery and bifid median nerve. Given the volar position of the structure, its proximal point of insertion, and its minimal bulk, we did not feel that this was the cause of our patients carpal tunnel syndrome.

A knotless bidirectional-barbed tendon repair is inferior to conventional 4-strand repairs in cyclic loading

We divided 21 flexor digitorum profundus tendons in the index, middle and ring fingers in seven cadaver hands into three groups. The tendons were cut in zone 2 and repaired using a 4-strand cruciate core suture repair with one of the following three materials in each group: (1) a knotless repair with a 2-0 bidirectional-barbed suture, which has similar tensile strength as a 4-0 non-barbed suture used in the other two groups; (2) a knotted locking repair with a non-barbed 4-0 conventional suture; and (3) a non-locking repair with a non-barbed 4-0 knotless suture. The repaired fingers were cyclically loaded through a simulated active range of motion to a 5 N load. We monitored and recorded the gap sizes at regular intervals during the test. The 2-0 bidirectional-barbed suture group and non-barbed suture groups developed gaps of 2.2 mm after 10 cycles and 2.4 mm after 20 cycles, respectively. Over 1000 cycles, the mean gaps were 3.2 mm in the 4-0 conventional suture group and 9.1 mm in the 2-0 bidirectional-barbed group. The tendons in the 2-0 bidirectional-barbed group gapped earlier, with statistically significant differences compared with those in the locking repair with a non-barbed 4-0 knotless suture group. The repair strength of the barbed suture technique was inferior to the cruciate repairs using a conventional 4-0 non-barbed suture tested in this cyclic-loading model. Level of evidence: Level V

A Multicenter, Prospective, Randomized, Pilot Study of Outcomes for Digital Nerve Repair in the Hand Using Hollow Conduit Compared With Processed Allograft Nerve

Background: Current repair options for peripheral nerve injuries where tension-free gap closure is not possible include allograft, processed nerve allograft, and hollow tube conduit. Here we report on the outcomes from a multicenter prospective, randomized, patient- and evaluator-blinded, pilot study comparing processed nerve allograft and hollow conduit for digital nerve reconstructions in the hand. Methods: Across 4 centers, consented participants meeting inclusion criteria while not meeting exclusion criteria were randomized intraoperatively to either processed nerve allograft or hollow conduit. Standard sensory and safety assessments were conducted at baseline, 1, 3, 6, 9, and 12 months after reconstruction. The primary outcome was static 2-point discrimination (s2PD) testing. Participants and assessors were blinded to treatment. The contralateral digit served as the control. Results: We randomized 23 participants with 31 digital nerve injuries. Sixteen participants with 20 repairs had at least 6 months of follow-up while 12-month follow-up was available for 15 repairs. There were no significant differences in participant and baseline characteristics between treatment groups. The predominant nerve injury was laceration/sharp transection. The mean ± SD length of the nerve gap prior to repair was 12 ± 4 mm (5-20 mm) for both groups. The average s2PD for processed allograft was 5 ± 1 mm (n = 6) compared with 8 ± 5 mm (n = 9) for hollow conduits. The average moving 2PD for processed allograft was 5 ± 1 mm compared with 7 ± 5 mm for hollow conduits. All injuries randomized to processed nerve allograft returned some degree of s2PD as compared with 75% of the repairs in the conduit group. Two hollow conduits and one allograft were lost due to infection during the study. Conclusions: In this pilot study, patients whose digital nerve reconstructions were performed with processed nerve allografts had significantly improved and more consistent functional sensory outcomes compared with hollow conduits.

Comparison of digital nerve sensory recovery after repair using loupe or operating microscope magnification

Our purpose was to determine whether there was a significant difference in sensory recovery after digital nerve repair using loupe magnification or an operating microscope. We identified patients aged 21–75 who had primary proper digital nerve repairs at least 24 months before our study. A total of 12 patients with 13 digital nerve injuries repaired with loupe magnification and nine patients with 12 digital nerve injuries repaired using the operating microscope, agreed to return for assessment by a therapist blinded to treatment. We found no significant difference in sensory recovery between the two groups as measured by static two-point discrimination, moving two-point discrimination, and Semmes–Weinstein monofilament. There were also no significant differences in average Disabilities of the Arm Shoulder and Hand or visual analogue pain scores. Level of evidence: IV

The Effect of Distal Radius Translation in the Coronal Plane on Forearm Rotation: A Cadaveric Study of Distal Radius Fractures

PURPOSE To determine the effect of lateral translation of the distal radius in the coronal plane on forearm rotation after distal radius fracture. METHODS Ten fresh cadaveric limbs underwent distal radius osteotomy just proximal to the distal radial-ulnar joint to simulate an extra-articular distal radius fracture. We used an Agee Wrist Jack external fixator to create increasing magnitudes of distal fragment lateral translation in 2-mm increments. Forearm rotation was measured using a 3-dimensional camera at each magnitude of lateral translation. RESULTS Total forearm rotation for the intact specimen and 2, 4, 6, and 8 mm (maximal) radial translations was 186° ± 53°, 188° ± 54°, 189° ± 55°, 190° ± 57°, and 193° ± 59°, respectively. There was no significant difference for any magnitude of radial translation. The average maximal radial translation possible before radioulnar abutment was 8 ± 0.5 mm. CONCLUSIONS In this cadaveric model, translation of the distal radius fragment in the lateral direction had no effect on forearm rotation. CLINICAL RELEVANCE At the level of the proximal border of the distal radioulnar joint, isolated distal radius translation does not significantly affect forearm rotation.

The quality of randomised controlled trials involving surgery from the hand to the elbow a critical analysis of the literature

Aims Our purpose was to determine the quality of current randomised controlled trials (RCTs) in hand surgery using standardised metrics. Materials and Methods Based on five‐year mean impact factors, we selected the six journals that routinely publish studies of upper extremity surgery. Using a journal‐specific search query, 62 RCTs met our inclusion criteria. Then three blinded reviewers used the Jadad and revised Coleman Methodology Score (RCMS) to assess the quality of the manuscripts. Results Based on the Jadad scale, 28 studies were of high quality and 34 were of low quality. Methodological deficiencies in poorly scoring trials included the absence of rate of enrolment, no power analysis, no description of withdrawal or dropout, and a failure to use validated outcomes assessments with an independent investigator. Conclusion A large number of RCTs in hand, wrist, and elbow surgery were of suboptimal quality when judged against the RCMS and Jadad scales. Even with a high level of evidence, study design and execution of RCTs should be critically assessed. Methodological deficiencies may introduce bias and lead to statistically underpowered studies.

Endoscopic Compared with Open Operative Treatment of Carpal Tunnel Syndrome

Carpal tunnel syndrome is the most common peripheral nerve compression syndrome. Treatment options include wrist-neutral bracing, corticosteroid injections, operative release of the transverse carpal ligament, and symptom-relief options. Endoscopic carpal tunnel release may give patients a faster recovery compared with traditional open release, but there are no ultimate differences in outcome among the various surgical options.

Viability of Hand and Wrist Photogoniometry

Background: No goniometric technique is both maximally convenient and completely accurate, although photogoniometry (ie, picture taking to facilitate digital angle measurement) shows promise in this regard. Our purpose was to test the feasibility and reliability of a photogoniometric protocol designed to measure wrist and digit range of motion in general. Methods: Two independent observers examined a sample of joints in both normal and abnormal hands according to a photogoniometric protocol. Interrater and intrarater correlation were calculated, and these measurements were compared with measurements made by a third independent examiner with a manual goniometer. Results: The photo-based measurements were reliable within and between observers; however, only a minority of these measurements were in agreement with manually collected values. Conclusions: At present, photogoniometry is not an acceptable alternative to manual goniometry for determining wrist and digit range of motion in general. Joint-specific photogoniometry should be the subject of future study, as should relevant imaging and software technology.