A Multicenter Prospective Randomized Comparison of Conduits Versus Decellularized Nerve Allograft for Digital Nerve Repairs

PURPOSE

While there are advantages and disadvantages to both processed nerve allografts (PNA) and conduits, a large, well-controlled prospective study is needed to compare the efficacy and to delineate how each of these repair tools can be best applied to digital nerve injuries. We hypothesized that PNA digital nerve repairs would achieve superior functional recovery for longer length gaps compared with conduit-based repairs.

METHODS

Patients (aged 18-69 years) presenting with suspected acute or subacute (less than 24 weeks old) digital nerve injuries were recruited to prticipate at 20 medical centers across the United States. After stratification to short (5-14 mm) and long (15-25 mm) gap subgroups, the patients were randomized (1:1) to repair with either a commercially available PNA or collagen conduit. Baseline and outcomes assessments were obtained either before or immediately after surgery and planned at 3-, 6-, 9-, and 12-months after surgery. All assessors and patients were blinded to the treatment arm.

RESULTS

In total, 220 patients were enrolled, and 183 patients completed an acceptable last evaluable visit (at least 6 months and not more than 15 months postrepair). At last follow-up, for the short gap repair groups, average static two-point discrimination was 7.3 ± 2.8 mm for PNA and 7.5 ± 3.1 mm for conduit repairs. For the long gap group, average static two-point discrimination was significantly lower at 6.1 ± 3.3 mm for PNA compared with 7.5 ± 2.4 mm for conduit repairs. Normal sensation (American Society for Surgery of the Hand scale) was achieved in 40% of PNA long gap repairs, which was significantly more than the 18% observed in long conduit patients. Long gap conduits had more clinical failures (lack of protective sensation) than short gap conduits.

CONCLUSIONS

Although supporting similar levels of nerve regeneration for short gap length digital nerve repairs, PNA was clinically superior to conduits for long gap reconstructions.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic I.

Outcomes Following Repeat Collagenase Treatment of Dupuytren Contracture

PURPOSE

Injectable collagenase Clostridium histolyticum has been an effective and well-tolerated nonsurgical treatment option for the management of Dupuytren contracture of the hand. The purpose of this study was to determine the efficacy of collagenase injection and adverse event rate in patients who had undergone previous collagenase treatment.

METHODS

A retrospective chart review was performed on 332 patients treated with collagenase injection for Dupuytren contracture by three fellowship-trained hand surgeons at a single institution from 2009 to 2019. Fifty-nine joints in 45 patients underwent repeat collagenase therapy for recurrent contracture in the same digit. Pretreatment and posttreatment total metacarpophalangeal and proximal interphalangeal joint flexion contractures were recorded, with complete correction defined as <5° residual digital flexion contracture. Postmanipulation skin tears and adverse events were recorded. A comparison was made between average contracture improvement after initial collagenase injection and that after repeat injection.

RESULTS

Forty-five patients with an average duration of 30 months (range, 6-73 months) between initial and repeat collagenase therapies were identified. The mean improvement after first collagenase injection was 45° ± 24° (39° for metacarpophalangeal joint and 50° for proximal interphalangeal joint) compared with a mean improvement of 43° ± 23° (41° for metacarpophalangeal joint and 44° for proximal interphalangeal joint) after second injection. Although similar complete correction rates and skin tear rates (32.2 % for initial and 30.5% for repeat) were observed between initial (80%) and repeat injections (73%), the occurrence of adverse events was 3 times higher (3.4% for initial and 10.2% for repeat) in the latter group.

CONCLUSIONS

Collagenase treatment of Dupuytren contracture yields effective total flexion contracture correction. Repeat collagenase treatment of previously treated digits yields similar deformity correction and complete correction rates but a higher incidence of adverse events.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

ORIF of Distal Humerus Fractures with Modern Pre-contoured Implants is Still Associated with a High Rate of Complications

BACKGROUND

The purpose of this study was to identify complications after operative treatment of distal humerus fractures with anatomic, pre-contoured, locking distal humeral plates. We hypothesized that these fractures have high complication rates despite the use of these modern implants.

MATERIALS AND METHODS

Between 2010 and 2018, 43 adult patients with a distal humerus fracture underwent open reduction and internal fixation (ORIF) at a Level I trauma center. Pre-operative variables, including medical comorbidities, mechanism of injury, open or closed fracture, AO/OTA fracture classification (Type A, B, or C), and nerve palsy, were recorded. Intra-operative variables including surgical approach, ulnar nerve transposition, and plate configuration were recorded. Anatomic, pre-contoured, locking distal humeral plates were used in all patients. Various plating systems were used based on surgeon preference and fracture pattern. Post-operative complications including infection, nonunion, malunion, painful implants, nerve palsy, heterotopic ossification, stiffness, and post-traumatic arthritis were recorded.

RESULTS

Most fractures were Type C (53%). The posterior olecranon osteotomy approach (51%) and parallel plate configuration (42%) were used in most cases. At a mean follow-up of 15 months, the complication rate was 61% (26/43 patients). Among all patients, 49% (21/43 patients) required a reoperation. Elbow stiffness (19%) was the most common complication followed by nerve palsy (16%). There were four fracture nonunions (9%), deep infections (9%), painful implants (9%), post-traumatic arthritis (9%), and heterotopic ossification (9%).

CONCLUSIONS

Distal humerus fractures treated with ORIF utilizing anatomic, pre-contoured, locking distal humeral plates have a high complication rate, with many requiring reoperation.

LEVEL OF EVIDENCE

Therapeutic Level IV.

Peripheral nerve repair throughout the body with processed nerve allografts: Results from a large multicenter study

BACKGROUND

Peripheral nerve damage resulting in pain, loss of sensation, or motor function may necessitate a reconstruction with a bridging material. The RANGER® Registry was designed to evaluate outcomes following nerve repair with processed nerve allograft (Avance® Nerve Graft; Axogen; Alachua, FL). Here we report on the results from the largest peripheral nerve registry to-date.

METHODS

This multicenter IRB-approved registry study collected data from patients repaired with processed nerve allograft (PNA). Sites followed their own standard of care for patient treatment and follow-up. Data were assessed for meaningful recovery, defined as ≥S3/M3 to remain consistent with previously published results, and comparisons were made to reference literature.

RESULTS

The study included 385 subjects and 624 nerve repairs. Overall, 82% meaningful recovery (MR) was achieved across sensory, mixed, and motor nerve repairs up to gaps of 70 mm. No related adverse events were reported. There were no significant differences in MR across the nerve type, age, time-to-repair, and smoking status subgroups in the upper extremity (p > .05). Significant differences were noted by the mechanism of injury subgroups between complex injures (74%) as compared to lacerations (85%) or neuroma resections (94%) (p = .03) and by gap length between the <15 mm and 50-70 mm gap subgroups, 91 and 69% MR, respectively (p = .01). Results were comparable to historical literature for nerve autograft and exceed that of conduit.

CONCLUSIONS

These findings provide clinical evidence to support the continued use of PNA up to 70 mm in sensory, mixed and motor nerve repair throughout the body and across a broad patient population.

Drains Are Not Beneficial in Primary Shoulder Arthroplasty

The purpose of this study was to determine if clinical differences exist between closed drainage use in primary shoulder arthroplasty and postoperative complications. A retrospective review was performed of all primary total shoulder and reverse total shoulder arthroplasty procedures at the authors' institution during a 2-year period. A total of 378 of 636 shoulder arthroplasty patients met inclusion criteria. Drains were used in 111 patients. The authors did not identify a significant relationship between drain use and postoperative complications. When complications were stratified just by the presence or absence of risk factors, irrespective of whether a drain was used, no significant relationship was identified. This study does not support the routine use of closed drainage systems in primary shoulder arthroplasty, including for patients with risk factors for potentially developing postoperative complications. [Orthopedics. 2019; 42(1):e29-e31.].

A comparison of percutaneous needle fasciotomy and collagenase injection for dupuytren disease

PURPOSE

To compare percutaneous needle fasciotomy (PNF) with collagenase injection in the treatment of Dupuytren contracture.

METHODS

A retrospective review was performed for patients with Dupuytren disease treated with PNF or collagenase. Range of motion, patient satisfaction, and complications were recorded.

RESULTS

There were 29 patients in the collagenase group with mean baseline contractures of 40° for 22 affected metacarpophalangeal joints and 50° for 12 affected proximal interphalangeal joints. The PNF group was composed of 30 patients with mean baseline contractures of 37° for 32 affected metacarpophalangeal joints and 41° for 18 affected proximal interphalangeal joints. All patients were observed for a minimum of 3 months. Clinical success (reduction of contracture within 0° to 5° of normal) was accomplished in 35 of 50 joints (67%) in the PNF group and in 19 of 34 joints (56%) in the collagenase group. Patient satisfaction was similar between groups. Only minor complications were observed, including skin tears, ecchymosis, edema, pruritus, and lymphadenopathy.

CONCLUSIONS

In the short term, both PNF and collagenase have similar clinical outcomes and patient satisfaction.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic III.

Complications following distal biceps repair

PURPOSE

Distal biceps rupture is a relatively uncommon injury. Surgical repair is performed in patients who seek increased flexion and supination strength over that which results from nonoperative treatment. The purpose of this study was to evaluate complications associated with surgical repair of the distal biceps tendon in a large series of patients.

METHODS

We retrospectively reviewed 198 consecutive patients with distal biceps ruptures treated with surgical repair, and evaluated time from injury to repair, surgical technique, and complications.

RESULTS

A total of 72 patients (36%) developed complications; 6 patients underwent additional surgery. Minor complications included lateral antebrachial cutaneous nerve paresthesia (26%), radial sensory nerve paresthesia (6%), and superficial infection (2%). Major complications included posterior interosseous nerve injury (4%), symptomatic heterotropic ossification (3%), and re-rupture (2%).

CONCLUSIONS

Minor complications were common after distal biceps tendon repair; however, most were sensory nerve injuries that resolved with time. Major complications were infrequent, and few patients required revision surgery. Complications were more common after distal biceps tendon repair performed more than 28 days after rupture.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Incidence and clinical outcomes of tendon rupture following distal radius fracture

PURPOSE

To evaluate the incidence of tendon rupture after nonoperative and operative management of distal radius fractures, report clinical outcomes after tendon repair or transfer, and examine volar plate and dorsal screw prominence as a predictor of tendon rupture.

METHODS

We performed a retrospective chart review on patients treated for tendon rupture after distal radius fracture. We evaluated active range of motion, Disabilities of Arm, Shoulder, and Hand score, grip strength, and pain score, and performed radiographic evaluation of volar plate and dorsal screw prominence in both the study group and a matched control group.

RESULTS

There were 6 tendon ruptures in 1,359 patients (0.4%) treated nonoperatively and 8 tendon ruptures in 999 patients (0.8%) treated with volar plate fixation. At the time of final follow-up, regardless of treatment, we noted that patients had minimal pain and excellent motion and grip strength. Mean Disabilities of the Shoulder, Arm, and Hand scores were 6 for patients treated nonoperatively and 4 for those treated with volar plating.

CONCLUSIONS

We were unable to verify volar plate or dorsal screw prominence as independent risk factors for tendon rupture after distal radius fractures. However, we recommend continued follow-up and plate removal for symptomatic patients who have volar plate prominence or dorsal screw prominence. In the event of tendon rupture, we report excellent clinical outcomes after tendon repair or tendon transfer.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Clinical outcomes of total wrist arthroplasty

PURPOSE

Current indications for total wrist arthroplasty include patients with symptomatic end stage posttraumatic wrist arthritis, rheumatoid arthritis, and Kienböck disease, as an alternative to wrist arthrodesis. Arthroplasty may have advantage over arthrodesis because of the ability to retain motion. The purpose of this study was to evaluate the short-term clinical outcomes and complications of the Maestro Total Wrist System.

METHODS

We report the results of a retrospective review of 23 total wrist prostheses implanted in 22 patients. We administered the visual analog pain scale and Mayo wrist and Disabilities of the Arm, Shoulder, and Hand questionnaires. We reviewed wrist motion, grip strength, radiographs, and complications.

RESULTS

At a mean follow-up of 28 months (range, 4-55 mo), the Disabilities of the Arm, Shoulder, and Hand score and Mayo wrist score were 31 and 54, respectively. Mean pain scores improved from 8.0 to 2.2. The mean wrist flexion-extension arc was 90°. Radiographs revealed no evidence of prosthetic loosening. Grip strength averaged 60% of the strength of the opposite hand. Complications occurred in 7 of 23 patients. One failure occurred as a result of deep infection in a patient with prior intercarpal fusion, and was successfully converted to a wrist fusion.

CONCLUSIONS

Total wrist arthroplasty performed for pancarpal arthritis as an alternative to wrist arthrodesis can yield successful outcomes with low short-term failure rates.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Design of novel N-(2,4-dioxo-1,2,3,4-tetrahydro-thieno[3,2-d]pyrimidin-7-yl)-guanidines as thymidine phosphorylase inhibitors, and flexible docking to a homology model

A novel class of thymidine phosphorylase (TP) inhibitors has been designed based on analogy to the enzyme substrate as well as known inhibitors. Flexible docking studies, using a homology model of human TP, of the designed N-(2,4-dioxo-1,2,3,4-tetrahydro-thieno[3,2-d]pyrimidin-7-yl)-guanidines as well as their synthetic precursors provide insight into the observed experimental trends in binding affinity.