Creating cement keyholes (i.e. drilling simple holes in cancellous bone to allow cement filling) is a practice used in multiple scenarios in orthopaedic surgery to ensure improved fixation between the bone-cement interface and as such between bone and prosthesis. It is most commonly used in hip arthroplasty to secure fixation of the cup to the acetabulum by drilling keyholes in acetabulum. However very little research has been conducted into what the dimensions of such cement keyholes should be. The following laboratory based research was performed to provide insight into the optimum dimensions of cement keyholes.

The investigator designed a novel arrangement to enable testing of keyholes. Beechwood block models were then made to this design testing keyholes of varying diameters and depths. These were cemented with acrylic bone cement and then loaded to failure. A finite system analysis was also performed.

Results show that stresses are concentrated at the base of the keyhole. As such increasing diameter of keyhole infers greater strength, but there is no relationship between depth and strength. This has been further confirmed with finite element analysis. We suggest the width of cement keyholes bears more importance than the depth and propose drilling wide but shallow keyholes.

We present our experience of managing patients with iatropathic brachial plexus injury after delayed fixation of a fracture of the clavicle. It is a retrospective cohort study of patients treated at our peripheral nerve injury unit and a single illustrative case report. We identified 21 patients in whom a brachial plexus injury occurred as a direct consequence of fixation of a fracture of the clavicle between September 2000 and September 2011.

The predominant injury involved the C5/C6 nerves, upper trunk, lateral cord and the suprascapular nerve. In all patients, the injured nerve was found to be tethered to the under surface of the clavicle by scar tissue at the site of the fracture and was usually associated with pathognomonic neuropathic pain and paralysis.

Delayed fixation of a fracture of the clavicle, especially between two and four weeks after injury, can result in iatropathic brachial plexus injury. The risk can be reduced by thorough release of the tissues from the inferior surface of the clavicle before mobilisation of the fracture fragments. If features of nerve damage appear post-operatively urgent specialist referral is recommended.

Cite this article: Bone Joint J 2013;95-B:106–10.

Introduction

A 68 year old female patient underwent a left total hip replacement for primary osteoarthritis in March 2004. She was referred back by her GP 5 years as she was struggling with mobility and felt there were mice in her hip. It was squeking so loudly that it could be hear at a distance of 25 metres. There was no history of any falls or dislocation in the last 5 years. The implant used was an Exeter/ABG ceramic total hip prosthesis with Palacos cement. This ladies discomfort in her hip had been always there. She never described herself as being satisfied with the THR. However, her discomfort had worsened terribly over the last year.

Introduction

Revision surgery is generally recommended for recurrent dislocation following Total hip arthroplasty (THA). However, dislocation following revision THA continues to remain a problem with further dislocation rates upto 28% quoted in literature.

We present early results of one of the largest series in U.K. using dual mobility cemented acetabular cup for recurrent hip dislocation.

Introduction

We propose that Total Hip Replacement with correction of fixed flexion deformity of the hip and exaggerated lumbar lordosis will result in relief of symptoms from spinal stenosis, possibly avoiding a spinal surgery. A sequence of patients with this dual pathology has been assessed to examine this and suggest a possible management algorithm.

There is a difference of opinion regarding the usefulness of MR Imaging as a diagnostic tool for triangular fibrocartilage complex (TFCC) tears in the wrist. Our aim was to determine the accuracy of direct magnetic resonance arthrography (MRA) in the diagnosis of triangular fibrocartilage complex (TFCC) tears of the wrist in a district general hospital setting.

In a retrospective review of 21 patients who presented with complains of wrist pain and following a clinical examination, all had direct MR arthrography of the wrist in our hospital in a 1.5Tesla scanner. All had a diagnostic arthroscopy within 2-4 months of the MR scan. All patients had chronic ulnar sided wrist pain, although only two had a definite history of trauma. The findings of each diagnostic method were compared, with arthroscopy considered the gold standard.

Twenty-one patients were studied (10 male: 11 female), mean age 42 years (range 27-71) years). Seventeen TFCC tears were diagnosed on arthroscopy. For the diagnosis of TFCC tears MRA had a sensitivity, specificity and accuracy of 67%.

Our results echoed the opinion of some of the previous investigators with an unacceptable sensitivity or specificity for a diagnostic tool. MR arthrography needs to be further refined as a technique before it can be considered to be accurate enough to replace wrist arthroscopy for the diagnosis of TFCC tears. Other centres have reported better accuracy, using more advanced MRI technology. Until this iswidely available at all levels of healthcare the results of MRI for the diagnosis of TFCC tears should be interpreted with caution.

Introduction

Elective Orthopaedics has been targeted by the UK Department of Health as a maximum six-month waiting time for operations could not be met. The National Orthopaedic Project was initiated as a consequence and Independent Sector Treatment Centres (ISTCs) and well established private hospitals were utilised to treat NHS long wait patients.

Both acute and chronic hamstring injuries are disabling injuries, and occur almost entirely to elite athletes. We report our experience in the management of injuries of this location. Twenty seven patients (29 injuries) were included in the present study. They completed a questionnaire detailing their pre-injury activity, injury mechanism, rehabilitation and a subjective assessment of their recovery. At clinical examination pain and hip motion were evaluated.

Hamstring injuries predominantly affect males on the left side. Most procedures carried out were explorations with limited debridement and suture of the tendon. One third of patients felt they had returned to 100% of their pre-injury level, and 33% felt they had returned to 80–90% of their pre-injury level, the rest varied between < 20–80%. 45% gave a value of zero on the visual analogue pain scale independent of activity, those who gave a value above this had pain during active sports but not at rest.

Early repair leads to a much better recovery of muscle function, especially when dealing with complete avulsions. Lesions to the origin of the hamstring can be successfully managed if a high suspicion for the condition exerted.

We aimed to audit the results of one stop fragility fracture risk assessment service at fracture clinic for non-hip fractures in 50–75 years old patients at Newcastle General Hospital. Currently, fewer than 30% of patients with fragility fractures benefit from secondary prevention in the form of comprehensive risk assessment and bone protection because of multifactorial reasons. We have a fragility fracture risk assessment service staffed by an Osteoporosis Specialist Nurse equipped with a DEXA scanner located at the fracture clinic itself.

We carried out a retrospective audit of 349 patients of 50–75 years with suspected non-hip fractures referred from A& E Department from October 2006 to September 2007. Patients over 75 years were excluded because as per NICE guidelines, they should receive bone protection without need of a DEXA scan.

Out of these 349 patients with suspected fractures, 171 had fragility fractures. Median age was 64 years. 69 patients had humerus fracture, 65 had forearm fracture and 23 patients had ankle fracture and 14 had metatarsal fractures. Fracture risk assessment was carried out in 120 (70%) patients. Thirty Seven (31%) patients had osteoporosis and bone protection was recommended to GP. 38 (32%) had osteopenia and lifestyle advice was provided. 45 (37%) had normal axial bone densitometry. 90% patients had DEXA scan at the same time of fracture clinic appointment. Patients with male gender, undisplaced fracture and fewer fracture clinic appointments were more likely to miss fracture risk assessment.

Our experience suggests that locating fragility fracture risk assessment service co-ordinated by an Osteoporosis Specialist Nurse at fracture clinic is an efficient way of providing secondary prevention for patients with fragility fractures. This can improve team communication, eliminate delay and improve patient compliance because of ‘One Stop Shop’ service at the time of fracture clinic appointment.

Purpose: To present results of a series of patients treated with Trapeziectomy, Ligament Reconstruction and Tendon Interposition for treatment of 1st CMC joint arthritis.

Methods: 59 patients (65 thumbs) from Single surgeons’ practice were prospectively followed by 2 independent observers who did not participate in the study. Patient demographics, occupation, handedness, symptoms and clinical findings were recorded. Objective assessment including pinch and grip strength was carried out by the Occupational therapists. Functional outcome assessment was done using questionnaire designed by senior author. Patients were asked to evaluate the operation using the subjective assessment component of Buck-Gramcko score. Radiographs were studied for Trapezial space and arthroplasty space. Analysis was carried out using SPSS statistical software.

Results: A total of 59 patients at an average age of 62 years were followed up for an average of 25 months. Six patients had bilateral procedures. Average follow up was 3.5 years with minimum follow up being 3 years. Osteoarthritis was the commonest diagnosis accounting for 53 (91%) patients and rheumatoid arthritis in 6 (9%) of patients. 48 cases (82%) were Stage IV and 15 cases (18%) Stage V. Mean duration of symptomsbefore the surgical intervention was 36 months. 3 patients developed superficial wound infection and 4 patients developed reflex sympathetic dystrophy. The results suggested pinch strength and grip strength improved to 50% and 22.5% respectively, as compared to pre-operative value.

Conclusion: Treatment options for 1st CMC joint arthritis have evolved over time. Many prospective randomized studies have shown lack of advantage of LRTI as compared to trapeziectomy alone, but these studies are not free from limitations. The present study is one of the largest reported single surgeon series and benefits from aprospectively maintained database with minimum 3 years follow up. The study rises above the existing limitations in the literature and reinforces concept of Ligament Reconstruction and Tendon Interposition.

Level of Evidence: Level II (Prospective study)

Objective: The aim of the study was to test the hypothesis that insertion of a total knee replacement (TKR) may effect range of motion as a consequence of excessive stretching of the retinaculae.

Methods: 8 fresh frozen cadaver knees were placed on a customised testing rig. The femur was rigidly fixed allowing the tibia to move freely through an arc of flexion. The quadriceps were loaded to 175N in their physiologic lines of action using a cable, pulley and weight system. The iliotibial tract was loaded with 30N. Tibiofemoral flexion and extension was measured using an optical tracking system. Monofilament sutures were passed along the fibres of the medial patellofemoral ligament (MPFL) and the deep transverse band in the lateral retinaculum with the anterior ends attached to the patella. The posterior suture ends were attached to ‘Linear Variable Displacement Transducers’. Thus small changes in ligament length were recorded by the transducers. Ligament length changes were recorded every 10° from 90° to 0° during an extension cycle. A transpatellar approach was used when performing the TKR to preserve the medial and lateral retinaculae. Testing was conducted on an intact knee and following insertion of a cruciate retaining TKR (Genesis II). Statistical analysis was performed using a two way ANOVA test.

Results: The MPFL had a mean behaviour close to isometric, while the lateral retinaculum slackened by a mean of 6mm as the knee extended from 60 degrees (Fig 1). After knee replacement there was no statistically significant difference seen in ligament length change patterns in the MPFL, however the lateral retinaculum showed significant slackening from 10 to 0°.

Conclusion: The data does not support the hypothesis that insertion of a TKR causes abnormal stretching of the retinaculuae. This result relates specifically to the TKR design tested.

Objective: The aim of this study was to test the hypothesis that malrotation of the femoral component following total knee replacement (TKR) may lead to patellofemoral complications as a consequence of excessive stretching of the retinaculae.

Methods: 8 fresh frozen cadaver knees were placed on a customised testing rig. The femur was rigidly fixed allowing the tibia to move freely through an arc of flexion. The quadriceps and iliotibial tract were loaded to 205N in their physiologic lines of action using a cable, pulley and weight system. Tibiofemoral flexion and extension was measured using an optical tracking system. Monofilament sutures were passed along the fibres of the medial patellofemoral ligament (MPFL) and the deep transverse band in the lateral retinaculum with the anterior ends attached to the patella. The posterior suture ends were attached to ‘Linear Variable Displacement Transducers’. Thus small changes in ligament length were recorded by the transducers. Ligament length changes were recorded every 10° from 90° to 0° during an extension cycle. A transpatellar approach was used when performing the TKR to preserve the medial and lateral retinaculae. Testing was conducted following insertion of a cruciate retaining TKR (Genesis II). The femoral component was rotated using a custom built intramedullary device. Ligament length changes were measured at neutral rotation, 5° internal and 5° external rotation. Statistical analysis was performed using a two way ANOVA test.

Results: Internal rotation resulted in the MPFL slackening a mean of 1.7mm from 70-0° extension (p< 0.001). External rotation resulted in the MPFL tightening a mean of 1.5mm over the same range (p< 0.01). The lateral retinaculum showed less significant differences.

Conclusion: External rotation resulted in smaller length changes than internal rotation. Patellar tilting as a result of internal rotation may be caused by MPFL slackening and not lateral retinacular tension, contrary to popular understanding.

Objective: This study tested the hypothesis that complications resulting from overstuffing the patellofemoral joint after total knee replacement (TKR) may be a consequence of excessive stretching of the retinaculae.

Methods: 8 fresh frozen cadaver knees were placed on a customised testing rig. The femur was rigidly fixed and the tibia moved freely through an arc of flexion. The quadriceps and iliotibial tract were physiologically loaded to 205N using a cable, pulley and weight system. Tibiofemoral flexion/extension was measured using an optical tracking system. Monofilament sutures were passed along the fibres of the medial patellofemoral ligament (MPFL) and the deep transverse band in the lateral retinaculum with the anterior ends attached to the patella. The posterior suture ends were attached to ‘Linear Variable Displacement Transducers’. Thus, small changes in ligament length were recorded by the transducers. Length changes were recorded every 10° from 90°- 0° during an extension cycle. A transpatellar approach was used when performing the TKR to preserve the medial and lateral retinaculae. Testing was conducted following insertion of a cruciate retaining TKR (Genesis II). The patella was resurfaced and various patellar thicknesses were achieved by placing 2mm thick nylon washers behind the ‘onlay’ button. The thicknesses measured were 2mm understuff, pre-cut thickness, 2 and 4mm overstuff. Statistical analysis was performed using a two way ANOVA test.

Results: Patellar understuff resulted in the MPFL slackening an average of 1.6mm from 60 to 0° (p< 0.05). Overstuffing the patella 2mm resulted in no significant length changes whereas 4mm overstuff resulted in a mean increase in MPFL length of 2.3mm throughout extension (p< 0.001). No significant length changes seen in the lateral retinaculum

Conclusion: Overstuffing the PFJ stretches the MPFL, because it attaches directly between two bones. The lateral retinaculum attaches to the relatively mobile ITT, so overstuffing does not stretch it.

Background: Locking plates are used frequently in distal tibial fractures. We tested two different types of locking compression plates (LCP): the metaphyseal plate (MP) and the distal tibial plate (DTP). We evaluated the strain imposed on an experimental tibial osteotomy, and the stability of plate-tibia (composite bone) construct using LCP-MP and LCP-DTP.

Materials and methods: Twin strain gauged special composite tibial bones were used to simulate the human tibiae. We tested 5 tibiae: one was used as control, two tibiae were tested using LCP-MP, and two with LCP-DTP. Strain was measured by subjecting each construct to a cyclic load of 700 N at 3 Hz in neutral, flexion, extension and torsion to simulate the normal walking cycle.

Results: When compared with the control tibia, strain during the neutral moment at the proximal and distal strain gauge site in the LCP-MP and LCP-DTP constructs decreased by 6.4%/−41.5% and −39%/−47%, respectively. In flexion, the strain increased consistently in both the proximal and distal strain gauge sites using the LCP-MP by 34% and 109%. Using the LCP-DTP, the strain at the proximal strain gauge site decreased by 0.2% and increased by 18% at the distal strain gauge site. In extension, strain decreased by 25% at the proximal strain gauge site, and by 60% at the distal strain gauge site in the LCP –MP construct. In the LCP-DTP construct, the strain decreased by 13% at the proximal strain gauge site, and by 21% at the distal strain gauge site. There were no statistically significant torsional differences between LCP-MP and LCP-DTP group (P=0.121). In this experimental setup, the LCP-DTPs offer greater control of strain than LCP-MPs. They also confer greater resistance to fracture macro-movements, and improved stiffness consistently in neutral, flexion, and torsion than LCP-MPs.

Conclusion: The strain from osteotomised tibiae stabilised with LCP-MPs and LCP-DTPs were close to the strain of the control tibia. Both these locking plates were equally good and conferred greater stiffness in all loading positions.

Purpose: Management of unstable or comminuted displaced fractures of the distal radius is difficult. We report our experience treating these fractures with AO volar plate fixation applying the principle of a volarulnar tension band platting. An attempt to introduce a new radiological classification for the accuracy of reduction is made. The classification includes 10 criteria.

Materials and Method: We reviewed clinically and radiologically 99 patients (101 fractures); 60 were type C and 41 were type A. The average follow up was 37 months (24 – 57). The average age was 46 years (19 – 81). Sarmiento’s modification of Gartland and Werley and Cooney’s modification of Green and O’Brien were used for clinical assessment. Lidstorm and Frykman used for radiological assessment.

Results: At final follow up the means of distal radius parameters were: volar tilt of 9°, radial inclination of 22°, radial height of 11mm and palmer cortical angle of 32°. The mean dorsiflexion was 61°, palmer flexion was 59°, pronation was 80° and supination was 76°. Grip strength was 86% of the opposite side. The average DASH score was 13.6. There was 13 poor results, 6 of them had a significant loss the initial reduction. There was significant correlation between our classification outcome and the clinical outcome.

Conclusion: AO volar plate fixation of unstable distal radius fractures provides a strong fixation that maintains reduction and allows early mobilisation.

Introduction: We present here the clinical features and management strategies of patients with gluteus medius and minimus enthesopathy.

Methodology: We studied seven patients with lateral hip pain and tenderness on palpation, worse over the tip of the greater trochanter. All of them had a positive Trendelenburg’s sign, and a transient relief of pain on injecting local anaesthetic in the abductor mechanism. All of these patients were tertiary referrals from the rheumatologists, who had at least once injected them with corticosteroids.

Results: Four of these seven patients underwent exploration. An insertional tendinopathy of the abductors was noted in all the patients, and was debrided. Two of the patients had, in addition, a tear in the gluteus medius tendon, which was repaired. One patient had an injection of local anaesthetic and Aprotinin in the abductor mechanism with resolution of symptoms.

Discussion: Gluteus medius and minimus enthesopathy is a distinct clinical entity. Although the condition has been described in the radiological literature, we were unable to find any reference to the orthopaedic management of this condition. We observed only a small number of patients, and we are thus unable to provide definite answers. Patients presenting with the above clinical features warrant consideration of the diagnosis of abductor enthesopathy. Ultrasound scan or MRI scan helps in confirming the diagnosis. At present, our management protocol involves injecting a local anaesthetic / Aprotinin in the abductor mechanism. However, we are cautious in injecting more than once, as, at operation, we have observed necrosis of the abductor mechanism at its insertion in two patients, similar to that described for Achilles tendon. If this fails, we undetake surgical exploration. The exact surgical procedure is difficult to predict and may involve debridement and repair of the pathological tendon.

Purpose: Management of the unstable or comminuted displaced fractures of the distal radius is difficult. We report our experience treating these fractures with AO volar plate fixation. An attempt to introduce a new radiological classification for the accuracy of surgical reduction is made. The classification includes 10 criteria and 100 points.

Methods: 124 patients had volar plate fixation performed between June 2000 and May 2003 using AO volar plate. We reviewed clinically and radiologically 101 patients; 60 were type C and 41 were type A (after failed conservative treatment). The average follow up is 37 months (24 – 57). The average age is 46 years (19 – 81). Postoperative regimen consisted of immediate physiotherapy and a wrist splint for three weeks. Cooney’s modification of Green and O’Brien and Sarmiento’s modification of Gartland and Werley were used for clinical assessment. Lidstorm and Frykman used for radiological assessment.

Results: At final follow up the means of distal radius parameters were: volar tilt of 9 degrees, radial inclination of 22 degrees, radial height is 11mm and palmer cortical angle of 32 degrees. The mean dorsiflexion was 61 degrees, palmer flexion was 59 degrees, pronation was 80 degrees and supination was 76 degrees. Grip strength was 86 percent of the opposite side. The average DASH score was 13.6. There was 14 poor results, 6 of them had significant loss the initial reduction. There was significant correlation between our classification and the clinical outcome.

Conclusion: AO volar plate fixation of unstable distal radius fractures provides strong fixation that maintains reduction and allows early mobilisation.

Background: The healthy, adult human disc is innervated but the nerves are restricted to the outer few millimetres of the annulus fibrosus. In degenerate discs with associated back pain, however, the nerves are more numerous and penetrate further in.

We have used a sheep model of intervertebral disc degeneration to monitor the presence and organisation of nerves in the disc as degeneration progresses. This model has been used to study morphological and bio-chemical changes of the disc as it degenerates, in addition to associated alterations in end-plate vascularity and vertebral bone remodelling. One aspect of this model which has not been studied to date is how the innervation of the disc may change with the onset of degeneration. This is the object of the present study.

Materials and Methods: Four-year old, skeletally mature Merino wether sheep (n=64) were divided randomly into lesion and control groups. A surgical incision was created in the anterolateral annulus in the L1–L2 and L3–L4 discs of the lesion group. The control group received the same retroperitoneal surgical approach but the annulus was not incised. Intact lumbar discs encompassed by adjacent vertebral bodies were removed at 3,6,12 and 26 months post operation. Specimens were fixed, decalcified and paraffin embedded before sectioning (7μ thick, vertical sagittal sections) and stained immunohistochemically with the neuronal marker, PGP9.5, together with standard histological stains.

Results: The incised region of the outer annulus underwent collagenous re-organisation, consistent with an active repair process as early as three months post-operatively. However, the inner annular lesion had a poor repair response and propagated with time, sometimes through to the nucleus. In contrast, remodelling of the outer annular lamellae occurred across the cut region. For example, in one sample at two years post injury there were up to six lamellae “bridging the gap”. Nerves were present in all samples but in the sham animals they were very few and confined to the very outer annulus or longitudinal ligament. In the operated animals, nerves were more extensive, occurring in the matrix adjacent to the fissure where there was often blood vessel ingrowth. The maximum number of nerves was seen at 12 months post-operatively, before diminishing in number at 24 months post-op. This paralleled the presence and extent of blood vessel penetration in this experimental model.

Conclusions: We have used an animal model to follow longitudinally the penetration of nerves into the ovine intervertebral disc in association with disc degeneration. Whilst we obviously cannot assess back pain in these animals, and not all nerves are nociceptive, nerves nevertheless are a pre-requisite for the perception of pain. Hence the greater numbers, size and penetration of nerves into degenerate discs demonstrated here has important implications not only for the aetiopathogenesis of degenerative disc disease but also for the treatment of its associated symptoms. Further characterisation of this innervation, i.e. whether autonomic or sensory, may provide an indication as to its nociceptive potential.