Moran, Steven L.

ABSTRACTFlexor tendon injuries are common and pose a clinical challenge for functional restoration. The purpose of our study was to assess the adequacy of the turkey as a large animal model for flexor tendon injuries in vivo. Twenty‐four male turkeys underwent surgical flexor tendon cut and repair. Turkeys were allocated to five groups postoperatively: (1) foot casted in extension and sacrificed after 3 weeks; (2) foot casted in extension and sacrificed after 6 weeks; (3) foot casted in flexion and sacrificed after 3 weeks; (4) foot casted in flexion and sacrificed after 6 weeks; and (5) foot casted in flexion for 6 weeks and then free roaming allowed for an additional 3 weeks before sacrifice. After sacrifice, digits were collected and analyzed for adhesion formation, healing at the macrolevel and histologically, and biomechanical properties—including friction, work of flexion, stiffness, and strength of repair. All turkeys survived anesthesia and surgery. Tendon rupture occurred in all extension casts and in 11% of those casted in flexion. Friction and work of flexion were significantly higher in the repaired digit than the control digit. There was a correlation between duration of immobilization and repair strength. Histologically, the tendon healed with tenocytes migrating into the gap and producing collagen fibers. We have, for the first time, studied flexor tendon injury and repair using turkeys in terms of anesthesia, surgical procedures, postoperative care, and animal husbandry. The findings regarding functional and histological results from this novel avian model were comparable to the most commonly used mammal model. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2497–2505, 2018.

AbstractIntroductionReconstruction of abdominal wall defects with enterocutaneous fistulas (ECF) remains challenging. The purpose of this report is to describe a single‐stage approach using combined microscopic enterolysis, pedicle seromuscular bowel flaps, mesh, fasciocutaneous, and myocutaneous flaps.MethodsBetween 1990 and 2016 a retrospective review identified a total of 18 patients with an average age of 39 years (ranging 26–59 years). Thirteen cases were associated with trauma, four were complication of previous mesh repair, and one was after an aortic dissection. Average diameter of defect size was 22 cm (ranging 20–24 cm). Surgical technique involved enterolysis using microscope magnification, a pedicle seromuscular bowel flap to reinforce the bowel anastomosis, mesh, musculocutaneous, and fasciocutaneous flaps to reconstruct the abdominal wall.ResultsFifteen patients required rotational flaps with an average skin paddle area of 442.7 cm2 (ranging 440 cm2–260 cm2) and 10 patients required a serosal patch with an average length of 5 cm (ranging 4–6 cm). Complications included three wound dehiscence and one abdominal wall bulging. Flap survival was 100%. The majority of patients (12 out of 18) were able to resume normal activities, and the remaining (n = 6) were able to resume most activities. Functional outcome as assessed by 36‐Item Short Form Survey (SF‐36) physical function component questionnaire at 18–24 months follow up was 67.8% (ranging from 59 to 72%). Mean length of hospital stay was 2.2 weeks (ranging 1.4–2.7 weeks). Mean follow‐up was 24 months (ranging 22–26 months) with clinical examination.ConclusionMicroscopically assisted intra‐abdominal dissection with resection of diseased bowel, replacement with well‐vascularized tissue at the anastomosis site in, and reinforcement with mesh combined with pedicle musculocutaneous and fasciocutaneous flaps may be an alternative when other local reconstructive options have failed.

Background: Salter-Harris fractures of the distal phalanx with or without clinical evidence of nail-bed laceration are frequently undertreated. Methods: A retrospective review was performed of all patients with distal phalanx Salter-Harris fractures treated between 2004 and 2016. Results: Seventy patients were treated for 72 Salter-Harris fractures at a mean ± SD age of 11.3 ± 3.7 years. Median follow-up was 6 weeks (interquartile range, 4 to 12.6 years). The thumb was most commonly involved (n = 21), followed by long (n = 18), ring (n =17), small (n = 9), and index (n = 7) fingers. Sport-related injuries accounted for 39 fractures (54 percent). Forty-two fractures (58 percent) had at least one clinical finding suggestive of nail-bed laceration (subungual hematoma, subluxation of the proximal nail plate, skin laceration proximal to the eponychial fold, bleeding from underneath the nail plate, eponychial fold laceration, and nail plate avulsion). Among 42 fractures with at least one feature of nail-bed laceration, surgical exploration was undertaken in 38 fractures. At exploration, a nail-bed laceration was found in 31 fractures (82 percent) and soft-tissue interposition was found in 18 (47 percent). Fractures with clinical features of nail-bed laceration (n = 42) were treated with open reduction and splinting (n = 25), open reduction and percutaneous pinning (n = 13), or splinting (n = 4). Excellent results were obtained, with few unfavorable outcomes. Infectious complications occurred in six patients. Conclusion: The high rate of nail-bed laceration and soft-tissue interposition in Salter-Harris fractures with clinical features of nail-bed laceration mandates surgical exploration. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

ABSTRACTThis study was to test our hypothesis that flexor tendon reconstruction with an allograft revitalized with bone marrow stromal cells (BMSCs) and synovialized with carbodiimide derivatized autologous synovial fluid (cd‐SYN) would result in better digit functional restoration than the conventional allograft tendon. A total of 32 flexor digital profundus tendons from the second and fifth digit of 16 dogs were created a repair failure model first. Then, failed‐repaired tendons were reconstructed with either a revitalized‐synovialized allograft tendon or a clinical standard autograft tendon (control group). The allograft tendon was seeded with autologous BMSCs in multiple slits and the graft surface was coated with cd‐SYN. A 6 weeks after tendon reconstruction, the digits were harvested and evaluated for digit function, adhesion status, tendon gliding resistance, attachment strength, cell viability, and histologic factors. The allograft group had significantly improved digit function compared with the control group through decreased work of flexion, increased digit range of motion under 2‐Newton force, and less adhesion score (p < .05). However, the distal attachment‐site strength and stiffness in the allograft tendon were significantly weaker than the autografts (p < .05). No significant difference was found for gliding resistance. Histologically, allograft tendons coated with allograft had smoother surfaces and showed tendon‐to‐bone and tendon‐to‐tendon incorporation. Viable BMSCs were found in the tendon slits 6 weeks after the graft. In conclusion, cellular lubricant‐based modification of allograft tendons improved digit function and reduced the adhesions compared with autograft for flexor tendon reconstruction. However, improvement of graft‐to‐host tendon healing is still challenging. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2218–2227, 2018.

Background: The medial femoral condyle free vascularized bone flap is a valuable alternative to other types of vascularized bone grafts. The donor-site morbidity and functional outcomes after flap harvest have not been fully appreciated. The authors report the postoperative outcomes and analyze the impact of increasing the size of the flap on knee donor-site morbidity. Methods: A retrospective chart review of patients who underwent medial femoral condyle flap surgery between 2001 and 2012 at their institution was performed. The size of the flap was stratified, based on the largest dimension, into three groups. Demographics, outcomes, and complications related to the flap donor site were recorded and analyzed. Subsequently, functional status was assessed by administering a validated condition-specific measure. A univariate logistic regression analysis was performed, and results were analyzed. Results: A total of 75 patients were identified. Average age was 29.5 ± 15.2 years. Average follow-up time was 13 months. The overall complication rate was 18.6 percent. Paresthesia in the saphenous nerve distribution was the most common complication. Increasing the size of the flap resulted in a significant elevation in complication risk (p < 0.05). A total of 47 patients completed the Lower Extremity Functional Scale questionnaire. The average Lower Extremity Functional Scale score was 72.12 ± 14.18. Fifty-one percent (n = 24) scored 80 points, indicating a normal level of function on average. Conclusions: The medial femoral condyle flap has overall acceptable donor-site morbidity, with a good level of function postoperatively. Larger flaps are associated with a greater number of complications. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Background: The vertical rectus abdominis myocutaneous flap has been used to reliably reconstruct posterior soft-tissue defects following resection of high sacral tumors, providing skin and soft-tissue bulk. Current literature examining the use of these flaps for high sacral reconstruction is limited. The purpose of this study was to report the authors’ institution's outcome on the use of the vertical rectus abdominis myocutaneous flap to reconstruct a high sacral defect following an oncologic resection. Methods: Eighty-seven patients (29 female and 58 male) underwent vertical rectus abdominis myocutaneous flap surgery to reconstruct a posterior wound following high sacral tumor resection from 1994 to 2016. The mean age and body mass index were 52 years and 27.8 kg/m2, respectively. The mean follow-up was 6 years. Results: Sixty-eight patients (79 percent) sustained a complication, most commonly a wound complication [n = 41 (47 percent)]. Twenty patients (23 percent) sustained a donor-site wound complication, most commonly a wound dehiscence (n = 10). Complications resulted in a reoperation in 44 patients (51 percent), with total flap failure occurring in one (1 percent). Preoperative radiotherapy and obesity were found to increase the risk of wound complications (p = 0.004 and p = 0.02, respectively) and deep infection (p = 0.03 and p = 0.02, respectively). Conclusions: Complications were common following vertical rectus abdominis myocutaneous flap surgery; however, total flap loss was not. Patients with obesity and preoperative radiotherapy should be cautioned on their increased risk of complications. Currently, the vertical rectus abdominis myocutaneous flap is the authors’ preferred means of soft-tissue reconstruction following high sacral tumor resection. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Background: Lower extremity intercalary allograft reconstruction has traditionally been used to facilitate limb salvage. Combining the allograft with a free vascularized fibula graft has been described; however, there is a paucity of data comparing the outcome of these reconstructions. Methods: Twenty-nine pediatric patients (15 boys and 14 girls) underwent lower extremity limb salvage with the use of intercalary cadaveric allograft at a mean age of 12 years. The most common diagnosis was osteosarcoma (n = 18). Patients underwent reconstruction with an allograft alone (n = 11) or supplemented with a free vascularized fibula graft (n = 18). Results: The mean time to union of the allograft was 11 months, with 10 patients requiring additional bone grafting. There was no difference in the need for an additional bone graft (OR, 0.87; p = 1.0) between patients with a free vascularized fibula graft and those without. The allograft was revised in three patients because of fracture (n = 2) and fracture and infection (n = 1). In all of these patients, the allograft was not supplemented with a free vascularized fibula graft (p < 0.001). Five patients underwent an amputation, most commonly for disease recurrence. At last follow-up, the mean Mankin and Musculoskeletal Tumor Society rating was 90 percent, with 19 patients (66 percent) who achieved a “good” or “excellent” outcome according to the Mankin score. Conclusion: Use of an intercalary allograft to reconstruct a lower extremity provides a durable means of reconstruction; however, supplementation with a free vascularized fibula graft reduces the risk of allograft revision. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Background: Distal radius fractures are common, and the trend in fixation has included the use of locked volar plating. The duration of splinting required after surgery and the effect splinting has upon outcome of the wrist are not clear. Our aim was to compare outcome of patients treated with early versus late motion protocol after volar plating. Methods: Thirty-three patients with distal radius fractures were prospectively and randomly enrolled into an early versus late motion study including volar plating of the distal radius fracture. Early motion included an active and passive wrist motion protocol by 14 days after surgery and delayed motion was initiated at 5 weeks. Fractures were defined as intra-articular and extra-articular, and those with, and without, ulnar styloid fracture. Motion and outcome scores (Disabilities of the Arm, Shoulder and Hand [DASH]/patient-rated wrist evaluation [PRWE]), and strength were measured through 1 year. Results: Wrist motion, DASH, and PRWE scores were only significantly different at 6 weeks with no significant differences at any later time points up to 1 year. One patient had complex regional pain syndrome (CRPS) and one had adhesive capsulitis in the late motion group. Conclusions: Following locked volar plating of distal radius fractures, early motion favored earlier return of motion along with lower DASH, PRWE, and pain scores within first 6 weeks. Although the late motion group had delayed recovery, there were no long-term significant differences in motion, strength, outcome, or pain scores. The 2 cases with complications (CRPS and adhesive capsulitis) did occur in the late motion group and may implicate late motion with these problems.

Tendon injuries are among the most common and severe hand injuries with a high demand for functional recovery. Stem cells have been identified and isolated from different species and a variety of tissues for the sake of regenerative medicine. Recently, turkey has been suggested as a potential new large animal model for flexor tendon-related research. However, turkey tissue-specific stem cells have not been investigated. Here, we presented the isolation and verification of tendon-derived stem cells (TDSCs) from 6- to 8-month-old heritage-breed turkey. TDSCs were isolated from turkey flexor tendon by plating nucleated cells at the determined optimal density. Approximately 4% of the nucleated cells demonstrated clonogenicity, high proliferation rate, and trilineage differentiation potential after induction culturing. These cells expressed surface antigens CD90, CD105, and CD44, but did not express CD45. There was a high level of gene expression of tenogenic markers in TDSCs, including mohawk, collagen type I, tenascin C, and elastin. Turkey TDSCs also expressed transcription factorsPouV,Nanog, andSox2, which are critically involved in the regulation of stemness. The successful isolation of tendon-derived stem cells from turkey was beneficial for future studies in tendon tissue engineering and would help in the development of new treatment for tendon diseases using this novel animal model.