We aim to determine the differences in lower limb joint kinematics during the golf swing of patients who had undergone Total Knee Arthroplasty (TKA) and a control group of native knee golfers.

A case-control study was undertaken with ten golfers who had undergone TKA (cruciate retaining single radius implant) and five age and matched golfers with native knees. Each golfer performed five swings with a driver whilst being recorded at 200Hz by a ten-camera motion capture system. Knee and hip three-dimensional joint angles (JA) and joint angular velocities (JAV) were calculated and statistically compared between the groups at six swing events.

The only significant differences in knee joint kinematics between TKA and control groups was a lower external rotation JA in the left knee during the backswing (p=0.010). There was no significant difference in knee JAV between the groups. Both hips demonstrated significantly (p=0.023 for left and p=0.037 for right) lower flexion in the TKA group during the takeaway swing event, and there was lower internal rotation in the backswing and greater external rotation in the downswing of the right hip. There was also slower left hip extension JAV in the downswing.

Normal knee kinematics were observed during the golf swing following TKA, with the exception of reduced external rotation in the left knee during the back swing and the right during the down swing. The differences demonstrated in the hip motion indicate that they may make compensatory movements to adjust to the reduced external rotation demonstrated in the knee.

Abstract

This prospective, randomized, controlled trial compares patient outcome after non-operative care versus open reduction and tunneled suspension device fixation (ORTSD) for grade III or IV acromioclavicular joint disruptions.

Sixty patients aged between sixteen and thirty-five years with an acute grade III or IV AC joint disruption were randomized to receive ORTSD fixation or non-operative treatment. Functional assessment was conducted at six weeks, three months, six months, and one year using the Disabilities of the Arm, Shoulder and Hands (DASH), Oxford Shoulder Scores (OSS) and Short Form (SF-12). Reduction was evaluated using radiographs. Complications were recorded, and an economic evaluation performed.

There was no significant difference in DASH or OSS at one year between non-operative and ORTSD groups (DASH score, 4.67 versus 5.63; OSS, 45.72 versus 45.63). Patients undergoing surgery had inferior DASH scores at 6 weeks (p<0.01). Five patients who failed non-operative management subsequently received surgery. Overall cost of treatment was significantly greater after ORTSD fixation (£796.22 vs £3359.73 (p<0.01)).

ORTSD fixation confers no functional benefit over non-operative treatment at one year. While patients managed non-operatively generally recover faster, a significant group remain dissatisfied following non-operative treatment requiring delayed surgical reconstruction.

Fractures of the lateral clavicle with complete displacement have a high non-union rate and are associated with poor functional outcomes following non-operative treatment. Various operative techniques are available but preliminary studies of open reduction and tunnelled suspensory device (ORTSD) fixation report good early functional outcomes with a low rate of complications. This study assesses the functional outcomes in a large series of patients treated using ORTSD.

After surgical reconstruction in 67 patients, outcomes were assessed using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire and Oxford score at six weeks, and three, six and twelve months post-operatively. 55 of 64 surviving patients were contacted at a mean of 69 (27–120) months to complete DASH and Oxford scores, evaluate overall satisfaction, and document any complications.

At one year post-operatively, the mean Oxford score was 46.4 and mean DASH score was 2.4 points (59/67 patients assessed). At a mean of 69 months after surgery, the mean Oxford score was 46.5 and mean DASH score was 2.2 (55 surviving and contactable patients). There were no significant differences between the one-year functional scores and those at the latest follow-up. Two patients developed symptomatic non-union requiring re-operation, and two developed an asymptomatic fibrous union not requiring surgery. The five-year survival when considering only obligate revision for implant-related complications was 97.0%.

ORTSD fixation for isolated displaced lateral-end clavicle fractures in medically-fit patients is associated with good functional outcomes, and a low rate of medium-term complications. Routine removal of the implant was not necessary.

This study aimed to evaluate the effect of clavicular shortening, measured by three-dimensional computerized tomography (3DCT), on functional outcomes and satisfaction in patients with healed, displaced, midshaft clavicle fractures up to one year following injury.

The data used in this study were collected as part of a multicenter, prospective randomized control trial comparing open reduction and plate fixation with nonoperative treatment for displaced midshaft clavicle factures. Patients who were randomized to nonoperative treatment and who had healed by one year were included. Clavicle shortening relative to the uninjured contralateral clavicle was measured on 3DCT. Outcome analysis was conducted at six weeks, three months, six months and one year following injury and included the Disabilities of the Arm, Shoulder and Hand (DASH), Constant and Short Form-12 (SF-12) scores, and patient satisfaction.

48 patients were included. The mean shortening of injured clavicles, relative to the contralateral side, was 11mm (+/− 7.6mm) with a mean proportional shortening of 8percnt;. Proportional shortening did not significantly correlate with the DASH (p>0.42), Constant (p>0.32) or SF-12 (p>0.08) scores at any time point. There was no significant difference in the mean DASH or Constant scores at any followup time point both when the cut off for shortening was defined as one centimeter (p>0.11) or two centimeters (p>0.35). There was no significant difference in clavicle shortening between satisfied and unsatisfied patients (p>0.49).

This study demonstrated no association between shortening and functional outcome or satisfaction in patients with healed, displaced, midshaft clavicle fractures up to one year following injury.

Background

There are currently no effective treatments for skeletal muscle fibrosis. Myofibroblasts are the major cellular effectors of fibrosis but their origin in muscle is unknown. We report that PDGFRβ (platelet derived growth factor receptor beta) Cre inactivates genes in murine PDGFRβ+ cells and myofibroblasts in muscle with high efficiency. We used this system to delete the integrin αv subunit because of the suggested role of multiple αv integrins as central mediators of fibrosis in multiple organs.

Scar tissue formation secondary to acute muscle injury, surgical wounding and compartment syndrome can result in significant functional impairment and predispose to further injury. The source of fibroblasts, and the molecular mechanisms driving their activation and persistence in skeletal muscle fibrosis are not known. We hypothesized that cells expressing PDGFRβ become fibroblasts in response to injury and that targeting αv integrins in these cells reduces skeletal muscle fibrosis.

We used double-fluorescent reporter mice to demonstrate that cells expressing PDGFRβ become activated myofibroblasts in response to cardiotoxin (CTX) induced skeletal muscle injury. Following injury, PDGFRβ+ cells moved from perivascular locations into the interstitium in a distribution characteristic of fibroblasts, and showed marked induction of fibroblastic genes including αSMA and collagen1 (all p<0.0001). To confirm that αv integrins present on PDGFRβ cells critically regulate skeletal muscle fibrosis we used Itgavflox/flox;PDGFRβ-Cre mice (transgenic mice in which αv integrins are ‘knocked-down’ in PDGFRβ+ cells). These mice were significantly protected from CTX induced fibrosis (p<0.01). To demonstrate potential clinical utility of targeting αv integrins, we used a small molecule inhibitor of αv integrins (CWHM12). Treatment with CWHM12 significantly reduced fibrosis when delivered from the time of injury (p<0.01) and when delivered after the fibrotic response had become established (p<0.01).

We have identified a core pathway regulating fibrosis in skeletal muscle. Pharmacologic inhibition of αv integrins has potential clinical utility in the treatment and prevention of skeletal muscle fibrosis.

Mesenchymal stem cells (MSCs) reside around blood vessels in all organs. This reservoir of progenitors can be ‘recruited’ in response to injury. The ability to manipulate stem cells therapeutically within injured tissue provides an attractive alternative to transplantation. Stem cells are regulated by neighbouring cells. We hypothesized that endothelial cells (ECs) influence MSC differentiation into bone and fat.

MSCs were sorted from fat using fluorescent activated sorting. Their capacity to differentiate into bone, fat and cartilage was used to confirm MSC phenotype. MSCs and ECs were cultured in two-dimensions (standard culture dishes) and three-dimensions (vascular networks suspended in gel). Cocultures were exposed to osteogenic and adipogenic media. The role of EC-released factors on MSC differentiation was determined using a system in which cells share media but do not contact. Wnt pathway modulators were used to investigate the role of Wnt signalling.

MSCs differentiated into bone, fat and cartilage. MSCs and ECs integrated in two- and three-dimensions. MSCs and ECs formed vessel-like structures in three-dimensions. When cultured with ECs, MSC differentiation to bone was accelerated while differentiation to fat was inhibited. This effect on osteogenesis was maintained when cells shared media but did not contact. Coculture with Wnt modulators confirmed that this effect is in part, mediated through Wnt signalling.

Our data suggest that ECs influence MSC differentiation. Therapeutic targeting of EC-MSCs signalling may enable manipulation of MSCs in vivo avoiding the need for cell transplantation. This could enable trauma and orthopaedic patients who have healthy resident stem cells to self-repair.

Adipose tissue is an attractive source of mesenchymal stem cells (MSCs) as it is largely dispensable and readily accessible through minimally invasive procedures such as lipoaspiration. Until recently MSCs could only be isolated in a process involving ex-vivo culture. Pericytes (CD45−, CD146+, and CD34−) and adventitial cells (CD45−, CD146−, CD34+) represent two populations of MSCs (collectively termed perivascular stem cells or PSCs) that can be prospectively purified using fluorescence activated cell sorting (FACS). We performed FACS on lipoaspirate samples from n=129 donors to determine the frequency and yield of PSCs and to establish patient and processing factors that influence yield.

The mean number of stromal vascular fraction (SVF) cells from 100ml of lipoaspirate was 37.8×106. Within the SVF, mean cell viability was 82%, with 31.6% of cells being heamatopoietic (CD45+). Adventitial cells and pericytes represented 31.6% and 7.9% of SVF cells respectively. As such, 200ml of lipoaspirate would theoretically yield 24.5 million MSCs –a sufficient number to enable point-of-care delivery for use in several orthopaedic applications. The yield and prevalence of PSCs were minimally affected by donor age, sex and BMI. Storing lipoaspirate samples for up to 72 hours prior to processing had no significant deleterious effects on MSC yield or viability.

Our study confirms that pure populations of MSC-precursors (PSCs) can be prospectively isolated from adipose tissue, in sufficient quantities to negate the necessity for culture expansion while widening possible applications to include trauma, where a time delay between extraction and implantation excludes their use.

Background

Non-union has traditionally been considered a rare complication following the non-operative management of clavicle fractures. A growing body of evidence has demonstrated higher rates of non-union in adults with displaced fractures. However, the variables that predict non-union in these patients remain unclear. We evaluated the prevalence and risk factors for non-union following displaced midshaft clavicle fractures in a large consecutive series of patients managed non-operatively in our Unit.

Background

Acute anterior dislocation of the glenohumeral joint may be complicated by injury to neighboring structures. These injuries are best considered a spectrum of injury ranging from an isolated dislocation (unifocal injury), through injuries associated with either nerve or osteoligamentous injury (bifocal injury), to injuries where there is evidence of both nerve and osteoligamentous injury. The latter combination has previously been described as the “terrible triad,” although we prefer the term “trifocal,” recognizing that this is the more severe end of an injury spectrum and avoiding confusion with the terrible triad of the elbow. We evaluated the prevalence and risk factors for nerve and osteoligamentous injuries associated with an acute anterior glenohumeral dislocation in a large consecutive series of patients treated in our Unit.

Non-union has traditionally been considered a rare complication following the non-operative management of clavicle fractures. Recent studies demonstrate higher rates of non-union in adults with displaced fractures, yet the variables predicting non-union remain unclear. We evaluated the prevalence and risk factors for non-union following displaced midshaft clavicle fractures in a large consecutive series of patients managed non-operatively.

1097 consecutive adults (mean age 26.1yrs) with displaced midshaft clavicle fractures treated non-operatively in our Unit were included. All patients were interviewed, examined and underwent radiological assessment within a week of injury. All patients were managed in a sling for two weeks followed by early mobilization. All patients were followed-up until clinical and radiological confirmation of union. Non-union was defined clinically as pain or mobility of the fracture segments on stressing, and radiologically as failure of cortical bridging by 6 months.

198 (18%) of patients had evidence of non-union at 6 months. Patient factors associated with non-union included increasing age, smoking and the presence of medical comorbidities (p<0.05). Injury-related factors associated with non-union included increasing fragment translation and displacement, and injury pattern (Edinburgh 2B2: comminuted segmental fracture)(p<0.01).

We present the largest series reporting prevalence and risk factors for non-union following conservatively treated, displaced midshaft clavicle fractures. These fractures can no longer be viewed as a single clinical entity, but as a spectrum of injuries each requiring individualized assessment and treatment. Increased understanding of the outcomes of these injuries will enable clinicians to better identify those patients that may be better served with primary operative reconstruction.

We reviewed 87 patients who underwent revision anterior cruciate ligament (ACL) reconstruction. The incidence of meniscal tears and degenerative change was assessed and related to the timing from primary ACL graft failure to revision ACL reconstruction. Patients were divided into either an early group (revision surgery within 6 months of graft failure) or a delayed group. Degenerative change was scored using the French Society of Arthroscopy system. There was a significantly higher incidence of articular cartilage degeneration in the delayed group compared to the early group (53.2% vs 24%, p < 0.01, Mann- Whitney U test). No patients in the early group had advanced degenerative change (SFA grades 3 or 4), compared with 12.9% of patients in the delayed group. There was no significant difference in the incidence of meniscal tears between the two groups. In conclusion, the findings of the study support the view that patients with a failed ACL reconstruction and symptomatic instability should have an early revision reconstruction procedure carried out to minimise the risk of articular degenerative change.