Impacted intraarticular fragments of distal radius fractures: A radiographic characterization and analysis of reliability and diagnostic accuracy.

BACKGROUND: Reduction using ligamentotaxis may not be effective enough to treat impacted intraarticular fragments of distal radius fractures. Articular incongruence resulting from the loss of reduction is a risk factor for postoperative osteoarthritis and worse clinical outcome. This study aimed to analyze the radiographic characterization of the impacted intraarticular fragments of distal radius fractures using two/three-dimensional computed tomography (CT). Further, we assessed the reliability and diagnostic accuracy in detecting the fragments using plain radiographs. METHODS: We analyzed 167 three-dimensional CT images of the intraarticular distal radius fractures and selected 12 fractures with impacted intraarticular fragments. We recorded the location, size, and displacement of the fragment using CT images. In addition, six examiners evaluated 25 fractures including those 12 fractures having the fragments using plain radiographs for detecting the fragments and their displacements. Further, we evaluated the reliability and diagnostic accuracy of the plain radiographs in the detection of the fragment. RESULTS: Fifteen impacted intraarticular fragments were found in 12 wrists. The displacement of the scaphoid facet fragment was significantly larger than that of the lunate facet fragment in CT measurement (7.0 mm and 3.6 mm). Inter and intraobserver reliability of the diagnosis for the fragment in plain radiographs were poor and fair (κ: 0.14 and κ:0.27). Diagnostic accuracy in detecting the fragment in plain radiographs generated mean sensitivity: 0.4, mean specificity: 0.73, and mean accuracy: 0.58. The mean sensitivity in detecting a lunate facet fragment was lower than that of a scaphoid facet fragment in plain radiographs (0.24 and 0.44). CONCLUSION: Impacted intraarticular fragments were found in 7% of intraarticular distal radius fractures. We observed low reliability and sensitivity in detecting the fragment using plain radiographs. Preoperative recognition of the fragments using plain radiograph were difficult, even though the magnitude of step-off of the scaphoid facet fragment was large.

Arthroscopic Lunate Excision Provides Excellent Outcomes for Low-Demand Patients with Advanced Kienböck's Disease.

PURPOSE: To examine the clinical outcomes of arthroscopic lunate excisions for advanced Kienböck's disease. METHODS: Fifteen patients (six men and nine women; mean age: 65 years; range: 48-83 years) with advanced Kienböck's disease, who underwent arthroscopic lunate resection between April 2008 and March 2016, were reviewed clinically and radiographically after a follow-up of >2 years (mean: 29 months; range: 24-60 months). Clinical parameters, such as wrist range of motion, grip strength, Disabilities of the Arm, Shoulder, and Hand (DASH) score, and patient-rated wrist evaluation (PRWE) score were evaluated. Radiographic parameters included radioscaphoid angle, scaphocapitate angle, carpal height ratio, ulnar-triquetrum distance, and the scaphoid-triquetrum distance. Wilcoxon's signed-rank test was used to compare measurement results. RESULTS: During the final follow-up, patients exhibited significant improvements, such as 42.9° in wrist range of motion (P = .009), 24.5% of the contralateral side in grip strength (P = .001), 26.2 points in DASH score (P = .002), and 37.8 points in PRWE score (P < .001), compared with the preoperative values. The radioscaphoid and scaphocapitate angles significantly increased by 4.8° (P = .0027) and 3.7° (P = .0012), respectively. The carpal height ratio, ulnar-triquetrum distance, and scaphoid-triquetrum distance significantly decreased by 0.05 (P < .001), 2.6 mm (P < .001), and 1.3 mm (P = .0012), respectively. CONCLUSIONS: Our results suggest that arthroscopic lunate excisions provided excellent postoperative pain relief and functional recovery within 2 years of follow-up. Changes in carpal alignment and stress concentration on the radial side of the carpal bones could occur in the long term; however, arthroscopic lunate excision can be a good surgical option for treating low-demand patients with advanced Kienböck's disease. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Biomechanical comparison of arthroscopic and open lunate excisions in the cadaveric wrist.

BACKGROUND: In advanced Kienböck disease, unreconstructible lunate should be excised as a salvage procedure. There is a lack of information about the biomechanical approaches evaluating the carpal kinematics after lunate excision. We hypothesized that arthroscopic lunate excision would not break the ring structure of the proximal carpal row, preventing carpal instability. We aimed to investigate changes in carpal kinematics following arthroscopic and open lunate excisions. METHODS: We used upper extremities from five fresh cadavers and simulated arthroscopic and open lunate excisions. Arthroscopic lunate excision was performed to preserve the attachment sites of intrinsic and extrinsic carpal ligaments to the lunate. Open lunate excision was conducted with sectioning of the intrinsic and extrinsic carpal ligaments. Using a three-dimensional space electromagnetic tracking device, rotation angles of the scaphoid and triquetrum and the change of scaphotriquetrum distance were measured under axial loading. We compared the rotation angles and the change of scaphotriquetrum distance among intact wrists, open, and arthroscopic lunate excisions. FINDINGS: No Significant differences in the rotation angle of the scaphoid and triquetrum or the change of scaphotriquetrum distance were found between intact wrist and arthroscopic lunate excision. The triquetrum significantly dorsiflexed and supinated in wrists with open lunate excisions compared with intact wrists. Significant differences in the change of scaphotriquetrum distance were found between intact and openly excised wrists and between arthroscopic and open excisions. INTERPRETATION: Arthroscopic lunate excision potentially prevented kinematic change of the proximal carpal row under axial loading by maintaining the integrity of attachment sites of carpal ligaments.

Robust method to create a standardized and reproducible atrophic non-union model in a rat femur.

OBJECTIVE: No evidence exists about which biological approach is more reliable for creating non-union model. We investigated how to create a reproducible atrophic non-union model in a rat femur. METHODS: We compared three groups: simple osteotomy (group A), partial periosteum cauterization (group B), and extensive periosteum and bone marrow resection (group C). RESULTS: All samples in group C demonstrated atrophic non-union in radiological, histological, and biomechanical analyses, however half of the samples in group B showed fracture healing at week 16. CONCLUSION: Extensive resection of periosteum and bone marrow is important for a reproducible atrophic non-union model in a rat femur.

Arthroscopic Distal Scaphoid Resection for Isolated Scaphotrapeziotrapezoid Osteoarthritis.

PURPOSE: To investigate the radiographic and clinical results of arthroscopic distal scaphoid resection for isolated scaphotrapeziotrapezoid (STT) osteoarthritis and analyze the radiographic parameters associated with the functional outcomes. METHODS: From 2008 to 2014, 17 wrists with symptomatic isolated STT osteoarthritis without carpal deformity underwent arthroscopic distal scaphoid resection. We evaluated visual analog scale (VAS) scores for pain, grip strength, pinch strength, and Patient-Rated Wrist Evaluation (PRWE) scores before surgery and at the final follow-up. We analyzed correlations between the resection height and the radiographic and functional outcomes. RESULTS: The average follow-up period was 42 months. The average VAS score improved from 6.1 ± 2.3 before surgery to 1.7 ± 1.9 after surgery. The average grip strength improved from 18 ± 6 to 19 ± 9 kg, pinch strength from 2.5 ± 1.1 to 4.4 ± 1.7 kg, and PRWE score from 52 ± 23 to 32 ± 24. Carpal deformity (C-L angle of > 15°) was seen in 2 patients at the final follow-up. The deformity was more likely to occur when the resection height was greater than 3 mm. CONCLUSIONS: Arthroscopic distal scaphoid resection alone can reduce pain and improve functional outcomes for early to mid-stage isolated STT osteoarthritis in patients without dorsal intercalated segment instability deformity. Resection of greater than 3 mm of the distal scaphoid may result in carpal malalignment. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Osteogenesis of osteogenic matrix cell sheets preserved in culture medium in a rat model.

Osteogenic matrix cell sheets (OMCSs) are ideal for bone regeneration. Transportation of OMCSs may be necessary, during which their osteogenic ability must be maintained. Here, we evaluated different media and temperatures for OMCS preservation. Bone marrow stromal/stem cells (BMSCs) were obtained from Fischer rats and analyzed for stem cell markers by flow cytometry. OMCSs were prepared from BMSCs by treatment with dexamethasone and ascorbic acid phosphate. After OMCS collection, they were stored in minimum essential medium (MEM) or Hank's balanced salt solution (HBSS) at 37, 22, or 4°C for 24 hours. Cell viability and cytotoxic effects in the preservation conditions were determined by adenosine triphosphate (ATP) contents and lactate dehydrogenase (LDH) release, respectively. Osteogenesis was assessed by subcutaneously implanting preserved OMCSs around ß-tricalcium phosphate ceramic disks into syngeneic rats. Implants were evaluated by alkaline phosphatase (ALP) activities, osteocalcin contents, and histology. Mesenchymal stem cells comprised 51% of primary cultured BMSCs. ATP contents were significantly different in OMCSs stored in MEM or HBSS at 22°C and 4°C. LDH release was significantly different in OMCSs stored in HBSS at 22°C and 4°C. The highest LDH release was observed in OMCSs stored in HBSS at 37°C. ALP activities and osteocalcin contents were the lowest in implanted OMCSs stored in HBSS at 37°C at four weeks after subcutaneous implantation. There was a significant difference in the osteocalcin levels of implanted OMCSs stored in MEM at 37°C and HBSS at 4°C. Abundant bone tissue around and inside disks was found in histological sections of OMCSs stored in all preservation conditions except for MEM and HBSS at 37°C. Maintaining the osteogenic ability of OMCSs during transport is important, and preservation of OMCSs in MEM or HBSS at 4°C or 22°C is a simple and inexpensive method.

Anatomical Study of the Popliteal Artery Perforator-Based Propeller Flap and Its Clinical Application.

There is lack of anatomical information regarding the cutaneous perforator of the popliteal artery and its connections with the descending branch of the inferior gluteal and profunda femoris arteries. The authors aimed to evaluate the anatomical basis of the popliteal artery perforator-based propeller flap from the posterior thigh region and to demonstrate their experience using this flap. Ten fresh cadaveric lower extremities were dissected following injection of a silicone compound into the femoral artery. The authors investigated the number, location, length, and diameter of cutaneous perforators of the popliteal artery. Based on the results, the authors treated three cases with a large soft-tissue defect around the knee using a popliteal artery perforator-based propeller flap. The authors found a mean of 1.9 cutaneous perforators arising from the popliteal artery, with a mean pedicle length of 6 cm and a mean arterial internal diameter of 0.9 mm, which were located at an average of 4 cm proximal to the bicondylar line. The most distal perforator consistently arose along the small saphenous vein and connected proximally with the concomitant artery of the posterior femoral cutaneous nerve, forming a connection with perforating arteries of the profunda femoris artery. A mean of 4.5 cutaneous perforators branched from the arterial connection sites. All clinical cases healed without any complications. The popliteal artery perforator-based propeller flap is reliable for reconstruction of soft-tissue defects around the knee. The flap should include the deep fascia and concomitant artery along with the posterior femoral cutaneous nerve for maintaining the blood supply.

Implantation of Bone Marrow Stromal Cell Sheets Derived from Old Donors Supports Bone Tissue Formation.

The purpose of this study was to evaluate the osteogenesis ability of osteogenic matrix cell sheets (OMCS) derived from old donor cells. Bone marrow stromal cells (BMSC) were obtained from young (7-week-old) and old (1-year-old) Fischer344 rats donors and cultured with modified Eagle's medium (MEM group) alone or containing dexamethasone (Dex; 10 nM) and ascorbic acid phosphate (AscP; 0.28 mM) (Dex/AscP group). We prepared four in vitro experimental groups: (1) young MEM, (2) young Dex/AscP, (3) old MEM and (4) old Dex/AscP. Cell proliferation and osteogenic marker mRNA expression levels were evaluated in vitro. To assess bone formation in vivo, the cells of each group were combined with beta tricalcium phosphate (TCP) disks followed by implantation in recipient rats. The in vitro study showed significant differences in the mRNA expression of osteocalcin, ALP, and BMP2 between MEM and Dex/AscP groups. Bone formation following implantation was observed upon histological analyses of all groups. TCP combined with OMCS (OMCS/TCP group) resulted in enhanced bone formation compared to that following combination with BMSC (BMSC/TCP). The osteocalcin content of the OMCS/TCP group 4 weeks after implantation was significantly higher than that in the BMSC/TCP construct for both young and old donors. The present study clearly indicated that OMCS could be generated from BMSCs of old as well as young donors using a mechanical retrieval method. Thus, through its usage of OMCS, this method may represent a potentially effective therapeutic option for cell-based therapy in elderly patients.

Bone regeneration with osteogenic matrix cell sheet and tricalcium phosphate: An experimental study in sheep.

AIM: To determine the effects of a cell sheet created from sheep bone marrow and tricalcium phosphate (TCP) on osteogenesis. METHODS: Bone marrow cells were harvested from a sheep and cultured in a minimal essential medium (MEM) containing ascorbic acid phosphate (AscP) and dexamethasone (Dex). After 2 wk, the formed osteogenic matrix cell sheet was lifted from the culture dish using a scraper. Additionally, harvested bone marrow cells were cultured in MEM only as a negative control group, and in MEM with AscP, Dex, and ß-glycerophosphate as a positive control group. For in vitro evaluation, we measured the alkaline phosphatase (ALP) activity and osteocalcin (OC) content in the media of the cultured cells from each group. For in vivo analysis, a porous TCP ceramic was used as a scaffold. We prepared an experimental group comprising TCP scaffolds wrapped with the osteogenic matrix cell sheets and a control group consisting of the TCP scaffold only. The constructs were implanted subcutaneously into athymic rats and the cell donor sheep, and bone formation was confirmed by histology after 4 wk. RESULTS: In the in vitro part, the mean ALP activity was 0.39 ± 0.03 mg/well in the negative control group, 0.67 ± 0.04 mg/well in the sheet group, and 0.65 ± 0.07 mg/well in the positive control group. The mean OC levels were 1.46 ± 0.33 ng/well in the negative control group, 3.92 ± 0.16 ng/well in the sheet group, and 4.4 ± 0.47 ng/well in the positive control group, respectively. The ALP activity and OC levels were significantly higher in the cell sheet and positive control groups than in the negative control group (P < 0.05). There was no significant difference in ALP activity or OC levels between the cell sheet group and the positive control group (P > 0.05). TCP constructs wrapped with cell sheets prior to implantation showed bone formation, in contrast to TCP scaffolds alone, which exhibited poor bone formation when implanted, in the subcutaneous layer both in athymic rats and in the sheep. CONCLUSION: This technique for preparing highly osteoinductive TCP may promote regeneration in large bone defects.

Importance of anterior humeral line for successful anatomical reduction in the surgical treatment of pediatric supracondylar humeral fractures.

Anterior humeral line (AHL) and tilting angle (TA) are used for the assessment of pediatric elbow sagittal plane alignment in surgical treatment of pediatric supracondylar humeral fracture. However, few studies exist that compare the reliabilities between these parameters. The purpose of this study is to determine whether measurements of radiographic parameters are reliable and useful for achieving anatomical reduction. In the current study, we demonstrated that the identifying the AHL location involves a simple and reliable measurement compared with TA. The intraoperative AHL identification is a good indicator for achieving anatomical reduction.

Treatment of Intra-articular Distal Radius Fractures.

This review of current literature discusses the morphology of the volar aspect of the distal radius; the surgical procedure, arthroscopic findings, and clinical results of a plate presetting and arthroscopic reduction technique for acute intra-articular fractures; and a novel simulation guidance system for malunited intra-articular fractures. Classification of intra-articular distal radius fractures is also discussed, focusing on central depression fracture fragments, associated soft tissue injuries, and results for measuring scapholunate distances at different sites. Problems of the distal radioulnar joint are reviewed, in particular, functional outcomes of the authors' prospective cohort study on unstable intra-articular fractures involving the distal radioulnar joint.

A Biomechanical Perspective on Distal Radioulnar Joint Instability.

Background The purpose of this article was to review the anatomy, kinematics of the distal radioulnar joint (DRUJ), and to discuss definition, classification, and diagnosis of DRUJ instability. Methods A biomechanical perspective on physical examination of DRUJ ballottement test was documented. Physiological dynamic DRUJ translation and differences of the translation following sequential ligament sectioning and changes in different forearm and wrist positions were demonstrated. The clinical significance of each ligament's contribution to joint stability in specific wrist positions was addressed. Conclusion Each ligament stabilizing the DRUJ contributed to joint stability depending on the direction (palmer or dorsal) and different positions of the wrist and forearm. DRUJ ballottement test in each wrist and forearm position may detect tears of specific ligament stabilizing the DRUJ.

Biomechanical study of distal radioulnar joint ballottement test.

We investigated the reliability and accuracy of the distal radioulnar joint (DRUJ) ballottement test using five fresh-frozen cadaver specimens in triangular fibrocartilage complex (TFCC)-intact, and TFCC-sectioned wrists. The humerus and proximal ulna were fixed. The ulna was allowed to translate in dorsopalmar directions without rotation, and the radius was allowed to move freely. Four sensors of a magnetic tracking system were attached to the radius and ulna, and the nails of each examiner's thumbs. Five examiners conducted the DRUJ ballottement test before and after TFCC sectioning. We used two techniques: With holding and without holding the carpal bones to the radius (holding and non-holding tests, respectively). We compared the magnitudes of bone-to-bone (absolute DRUJ) movement with that of the examiner's nail-to-nail (relative DRUJ) movement. The intrarater intraclass correlation coefficients (ICCs) were 0.92 (holding) and 0.94 (non-holding). The interrater ICCs were 0.84 (holding) and 0.75 (non-holding). Magnitudes of absolute and relative movements averaged 11.5 and 11.8 mm, respectively (p < 0.05). Before TFCC sectioning, the DRUJ movement during the holding and non-holding techniques averaged 9.8 and 10.8 mm, respectively (p < 0.05). The increase in DRUJ movement after TFCC sectioning was greater with the holding technique (average 2.3 mm) than with the non-holding technique (average 1.6 mm). The DRUJ ballottement test with magnetic markers is relatively accurate and reliable for detecting unstable joints. We recommend the holding technique for assessing DRUJ instability in clinical practice. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1123-1127, 2017.

Septic arthritis of the wrist caused by Mycobacterium intracellulare: a case report.

Septic arthritis of the wrist is rare entity, especially; atypical mycobacterial infection of the wrist is extremely rare. We report a case of septic arthritis of the wrist caused by Mycobacterium intracellulare, which was successfully treated by radical debridement followed by wrist arthrodesis using vascularised fibular grafting.

Patient-based outcomes following surgical debridement and flap coverage of digital mucous cysts.

PURPOSE: The purpose of this prospective cohort study was to evaluate patient-based outcomes and complications following excision of mucous cysts, joint debridement, and closure with one of three types of local flaps. METHODS: From 2000-2011, 35 consecutive patients with 37 digital mucous cysts were treated surgically. The surgical procedure included excision of the cyst together with the attenuated skin, joint debridement on the affected side including capsulectomy, and removal of osteophytes. Depending on the size and location of the cyst, the skin defect was covered by a transposition flap (31 cysts), an advancement flap (two cysts), or a rotation flap (four cysts). RESULTS: At an average follow-up time of 4 years, 4 months, there was no wound infection, flap necrosis, or joint stiffness. Preoperative nail ridging resolved in seven of nine fingers, and no nail deformities developed after surgery. One cyst, treated with a transposition flap, recurred 10 months after surgery. The average satisfaction score for the affected finger significantly improved from 4.3 to 6.8, and the average pain score decreased from 4.7 to 2.3. CONCLUSION: This treatment protocol provides reliable results. Patients were satisfied with the reduction of associated pain and the postoperative appearance of the treated finger, and postoperative complications were minimal.

Effectiveness of Bone Marrow Stromal Cell Sheets in Maintaining Random-Pattern Skin Flaps in an Experimental Animal Model.

BACKGROUND: Bone marrow stromal cells can be applied therapeutically to enhance angiogenesis; however, the use of bone marrow stromal cell suspensions reduces efficiency because of low-level attachment. The authors hypothesized that bone marrow stromal cell sheets would facilitate cell fixation, thus enhancing angiogenesis. The authors investigated flap survival area and enhancement of angiogenic factors in a rat random-pattern skin flap model after application of bone marrow stromal cell sheets. METHODS: Bone marrow stromal cell sheets (prepared from 7-week-old rat femurs) were cultured under four different hypoxic conditions. Sheets with the highest angiogenic potential, determined by an in vitro pilot study, were injected into subcutaneous layers of the rat dorsum (bone marrow stromal cell sheet group). A control group (phosphate-buffered saline only) was included. On day 2 after injection, caudally based random-pattern skin flaps (12 × 3 cm) were elevated. On day 7 after elevation, surviving skin flap areas were measured. Skin samples were harvested from each flap and gene expression levels of vascular endothelial growth factor and basic fibroblast growth factor were measured by quantitative real-time polymerase chain reaction. RESULTS: Skin flap survival area (71.6 ± 2.3 percent versus 51.5 ± 3.3 percent) and levels of vascular endothelial growth factor and basic fibroblast growth factor were significantly higher in the bone marrow stromal cell sheet group than in the control group (p < 0.05). CONCLUSIONS: Implantation of bone marrow stromal cell sheets increased the survival area of random-pattern skin flaps. Expression of angiogenic factors may have contributed to the increased flap survival.

Predictors of Postoperative Finger Stiffness in Unstable Proximal Phalangeal Fractures.

BACKGROUND: The purpose of this study was to determine the risk factors for postoperative finger stiffness after open reduction and internal fixation of unstable proximal phalangeal fractures using a low-profile plate and/or screw system. We hypothesized that dorsal plate placement is a risk factor for postoperative finger stiffness. METHODS: Seventy consecutive patients (50 men, 20 women; average age, 40 years) with 75 unstable proximal phalangeal fractures were treated with titanium plates and/or screws and evaluated at a minimum follow-up of 1 year. Thirty-six comminuted fractures and 24 intra-articular fractures were included, and 16 fractures had associated soft-tissue injuries. Plate fixation was performed in 59 fractures, and the remaining 16 were fixed with screws only. The implants were placed in a dorsal location in 33 fractures and in a lateral or volar location in 42 fractures. Finger stiffness was defined as a total active range of finger motion <80% for the treated finger. Univariate and multivariate analyses were performed on 8 variables: patient characteristics (age and sex), fracture characteristics (fracture comminution, joint involvement, and associated soft-tissue injury), and surgical characteristics (type and location of implants and removal of the implants). RESULTS: Postoperative finger stiffness occurred in 38 fractures. The multivariate analysis indicated that plate fixation (odds ratio, 5.9; 95% confidence interval, 1.5-24.0; P = 0.01) and dorsal placement (odds ratio, 3.0; 95% confidence interval, 1.1-8.3; P = 0.03) were independent risk factors for finger stiffness. CONCLUSION: We recommend the use of screw fixation as much as possible for unstable proximal phalangeal fractures using a midlateral approach.

Ultrasound-guided Selective Sensory Nerve Block for Wide-awake Forearm Tendon Reconstruction.

BACKGROUND: Wide-awake hand surgery is useful for tendon reconstruction because surgeons can observe the actual movement of the reconstructed tendons during the surgery. We hypothesized that accurate ultrasound-guided injection of local anesthetics into the sensory nerves contributes to reliable analgesia with a relatively small amount of anesthetic. METHODS: We enrolled 8 patients who underwent forearm tendon transfer. Three patients underwent reconstruction of flexor tendon ruptures in zones 4 and 5, 3 underwent opponensplasty, and 2 underwent multiple tendon transfers according to Brand's procedure. All patients underwent ultrasound-guided injection of ropivacaine to each sensory nerve branch of the upper arm and forearm and into the subfascial layer of the forearm. The mean amount of total ropivacaine was 193 mg. RESULTS: In 7 of the 8 patients, we confirmed adequate active contraction of the flexor or extensor muscles during surgery. The expected active motion of the flexor pollicis longus was not found in 1 patient during surgery because the effect of the anesthetic had spread too widely, involving the motor branch of the median nerve. Two patients required additional infiltration of 2-3 mL of local anesthetic because of local wound pain. All patients gained satisfactory function of the transferred tendons after the surgery, and no remarkable perioperative complications related to local anesthetic systemic toxicity occurred. CONCLUSIONS: Selective administration of an anesthetic to the sensory nerve branches and subfascial layer enables the performance of wide-awake forearm tendon surgery. The ultrasound-guided injection technique provides safe and effective regional anesthesia for wide-awake surgery.

The regeneration and augmentation of bone with injectable osteogenic cell sheet in a rat critical fracture healing model.

Limitations in the current treatment strategies make cases with compromised bone healing challenging clinical problems. Osteogenic cell sheets (OCSs), fabricated from rat bone marrow stromal cells (BMSCs), contain enriched osteoblasts and extracellular matrix. Here, we evaluated whether the minimally invasive percutaneous injection of OCSs without a scaffold could be used as a treatment to increase bone regeneration in a critical fracture healing model. Critical fracture healing model was created in the femora of 60 male Fischer 344 inbred rats using marrow ablation and periosteal removal. The rats were then randomly divided into two groups. Six hours after fracture, one group received an injection of OCSs (OCS group), while the second group was injected with phosphate-buffered saline (PBS) (control group). Fracture healing was evaluated using radiological, histological, micro-computed tomography (CT) and biomechanical analyses. The radiological and histological evaluations demonstrated enhanced bone regeneration in the OCS group compared with that in the control group. By 12 weeks, the hard callus had been remodelled via recorticalization in the OCS group. By contrast, no fracture union was found in the rats in the control group. Biomechanical testing revealed a significantly higher maximum bending load in the OCS group compared with that in the control group. The results of the present study demonstrate that the injection of entire OCSs can enhance bone regeneration and lead to bony union in a critical fracture healing model. Therefore, this procedure offers a minimally invasive technique to promote hard tissue reconstruction and, in particular, bone repair strategies for cases with compromised bone healing.

Biceps femoris musculocutaneous flap for reconstruction of refractory ulceration at the popliteal fossa.

BACKGROUND: There is a lack of information about the possibility of transfer of the long head of the biceps femoris (LHBF) musculocutaneous flap to the knee area. We discuss the use of the LHBF musculocutaneous flap to treat refractory ulceration at the popliteal fossa and the results of a preliminary study investigating the anatomical possibility of transferring this flap to the popliteal region. METHODS: Five lower extremities of 5 fresh cadaveric specimens were dissected following injection of a silicone compound into the deep femoral artery. We investigated the number, location, and diameter of nutrient branches to the LHBF originating from the deep femoral artery. Based on these results, we treated a 76-year-old woman with a refractory postradiation ulcer at the popliteal fossa associated with popliteal artery obstruction using a 25 × 7 cm LHBF musculocutaneous flap. RESULTS: The mean number of nutrient branches to the LHBF muscle was 3.6, with a mean diameter of 1.9 mm. One to two branches consistently arose from the distal aspect of the posterior thigh. Most branches followed an intramuscular route, giving rise to fine cutaneous branches. The distal border reached by the musculocutaneous flap was located 6.7 cm distal to the bicondylar line. The flap survived completely without complications, and the patient was able to walk with a walking frame postoperatively. CONCLUSIONS: The LHBF musculocutaneous flap may offer a reliable treatment option for soft-tissue defects of the popliteal fossa, especially in patients with significant damage to the popliteal artery from trauma or radiation therapy.