Hip resurfacing arthroplasty (HRA) is a bone conserving alternative to total hip arthroplasty. We present the early 2-year clinical and radiographic follow-up of a novel ceramic-on-ceramic (CoC) HRA in an international multi-centric cohort.

Patients undergoing HRA between September 2018 and January 2021 were prospectively included. Patient-reported outcome measures (PROMS) in the form of the Forgotten Joint Score (FJS), HOOS Jr, WOMAC, Oxford Hip Score (OHS) and UCLA Activity Score were collected preoperatively and at 1- and 2-years post-operation. Serial radiographs were assessed for migration, component alignment, evidence of osteolysis/loosening and heterotopic ossification formation.

200 patients were identified to have reached 2-year follow-up. Of these, 185 completed PROMS follow-up at 2 years. There was significant improvement in HOOS (p< 0.001) and OHS (p< 0.001) and FJS (p< 0.001) between the pre-operative and 2-year outcomes. Patients reported improved pain (p<0.001), function (p<0.001) and reduced stiffness (p<0.001) as measured by the WOMAC score. Patients had improved activity scores on the UCLA Active Score (P<0.001) with 53% reporting return to impact activity at 2 years. There was no osteolysis and the mean acetabular cup inclination angle was 41deg and the femoral component shaft angle was 137deg. No fractures were reported over but there was one sciatic nerve palsy with partial recovery. Two patients were revised; one at 3 months for pain due to a misdiagnosed back problem and another at 33 months for loosening of the acetabular component with delamination of the titanium ingrowth surface.

CoC resurfacing at 2-years post-operation demonstrate promising results with satisfactory PROMS.

Aims

Femoral periprosthetic fractures are rising in incidence. Their management is complex and carries a high associated mortality. Unlike native hip fractures, there are no guidelines advising on time to theatre in this group. We aim to determine whether delaying surgical intervention influences morbidity or mortality in femoral periprosthetic fractures.

Hip resurfacing arthroplasty (HRA) is a bone conserving alternative to total hip arthroplasty. We present the early 1 and 2-year clinical and radiographical follow-up of a novel ceramic-on-ceramic (CoC) HRA in a multi-centric Australian cohort.

Patient undergoing HRA between September 2018 and April 2021 were prospectively included. Patient-reported outcome measures (PROMS) in the form of the Forgotten Joint Score (FJS), HOOS Jr, WOMAC, Oxford Hip Score (OHS) and UCLA Activity Score were collected preoperatively and at 1- and 2-years post-operation. Serial radiographs were assessed for migration, component alignment, evidence of osteolysis/loosening and heterotopic ossification formation.

209 patients were identified of which 106 reached 2-year follow-up. Of these, 187 completed PROMS at 1 year and 90 at 2 years. There was significant improvement in HOOS (p< 0.001) and OHS (p< 0.001) between the pre-operative, 1-year and 2-years outcomes. Patients also reported improved pain (p<0.001), function (p<0.001) and reduced stiffness (p<0.001) as measured by the WOMAC score. Patients had improved activity scores on the UCLA Active Score (p<0.001) with 53% reporting return to impact activity at 2 years. FJS at 1 and 2-years were not significantly different (p=0.38). There was no migration, osteolysis or loosening of any of the implants. The mean acetabular cup inclination angle was 41.3° and the femoral component shaft angle was 137°. No fractures were reported over the 2-year follow-up with only 1 patient reporting a sciatic nerve palsy.

There was early return to impact activities in more than half our patients at 2 years with no early clinical or radiological complications related to the implant. Longer term follow-up with increased patient numbers are required to restore surgeon confidence in HRA and expand the use of this novel product.

In conclusion, CoC resurfacing at 2-years post-operation demonstrate promising results with satisfactory outcomes in all recorded PROMS.

Cement-in-cement revision of the femoral component represents a widely practiced technique for a variety of indications. In this study we compare the clinical and radiological outcomes of two polished tapered stems.

From our prospectively collated database we identified all patients undergoing cement-in-cement revision from January 2005 – 2013 who had a minimum of two years follow-up. All cases were performed by the senior author using either an Exeter short revision stem or the C-stem AMT high offset No 1. Patients were followed-up annually with clinical and radiological assessment.

Ninety-seven patients matched the inclusion criteria. There were 50 Exeter and 47 C-stem AMT components. There were no significant differences between the patient demographics in either group. Mean follow-up was 9.7 years. A significant improvement in OHS, WOMAC and SF-12 scores was observed in both cohorts. Leg lengths were significantly shorter in the Exeter group, with a mean of -4mm in this cohort compared to 0mm in the C-stem AMT group. One patient in the Exeter group had early evidence of radiological loosening. In total, 16 patients (15%) underwent further revision of the femoral component (seven in the C-stem AMT group and nine in the Exeter group). No femoral components were revised for aseptic loosening. There were two cases of femoral component fracture in the Exeter group.

Our series shows promising long-term outcomes for the cement-in-cement revision technique using either the Exeter or C-stem AMT components. These results demonstrate that cement-in-cement revision using a double or triple taper-slip design is a safe and reliable technique when used for the correct indications.

Introduction

Acetabular cup orientation has been shown to be a factor in edge-loading of a ceramic-on-ceramic THR bearing. Currently all recommended guidelines for cup orientation are defined from static measurements with the patient positioned supine. The objectives of this study are to investigate functional cup orientation and the incidence of edge-loading in ceramic hips using commercially available, dynamic musculoskeletal modelling software that simulates each patient performing activities associated with edge-loading.

Introduction

Tendons are critical to mobility, and are susceptible to degeneration through injury and ageing. Type I collagen is the most abundant protein in vertebrates; it is the main structural protein of the extracellular matrix in numerous musculoskeletal tissues, including tendons. Type I collagen predominantly is a heterotrimer, which consists of two alpha-1 chains and one alpha-2 chain (α1)₂(α2) encoded by the COL1A1 and COL1A2 genes, respectively. However, type I collagen can form homotrimers (α1)₃ which are protease-resistant, and are associated with age-related musculoskeletal diseases, fibrotic and connective tissue pathologies. Transforming growth factor beta (TGFβ) enhances collagen (I) gene expression, is involved in tendon mechanobiology and repair processes, while its effect on homotrimer formation is unknown. Our aim is to investigate the relative expressions of collagen (I) α1 and α2 polypeptide chains in tenocytes (tendon fibroblasts) stimulated with TGFβ.

Multiple organ failure (MOF) is a major cause of trauma mortality and morbidity. The role of surgical procedures in precipitating MOF remains unclear.

Data on timing and duration of surgery was collated on 491 consecutive patients admitted to a Major Trauma Centre, who survived more than 48 hours and required Intensive Care Unit admission. MOF was defined according to the Denver Post Injury MOF Score, where MOF can occur only later than 48 hours after injury to exclude physiological derangements resulting from inadequate resuscitation.

Overall, 268 patients (54.6%) underwent surgery within 48 hours of injury, with 110 (22.4%) requiring surgery within 6 hours of injury. Total mean intra-operative time (p=0.067) nor the need for an operation within the first 6 (p=0.069) or 48 hours (p=0.124) were associated with MOF development. Multivariate predictive modelling of MOF showed timing and duration of surgery had no significant predictive power for MOF development (Odds Ratio 0.72, 95% CI 0.47–1.10).

Despite previous indication that early surgical intervention can precipitate MOF, current surgical strategy does not appear to impact MOF development.

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.

Introduction: Growing pains are a common complaint in school age children, but no definite organic causes have been identified. An association between musculoskeletal pain and joint laxity has been proposed. This study therefore investigates the relationship between growing pains and joint hypermobility in children.

Materials and Methods: Thirty three children with growing pains and thirty one controls of similar age and sex were recruited from outpatient clinics of a specialist paediatric hospital. Joint hypermobility was assessed in each group using the Beighton score. A Beighton score of greater than or equal to 4 out of 9 was considered hypermobile.

Results: The median Beighton scores were 6 for the study group and 0 for the control group. 93.3% of the study group had a Beighton score of equal to or greater than 4, compared to 22.6% of the control group. There was a highly significant difference in Beighton score between the two groups (P< 0.0001), with an estimated difference of 4 points 95% CI 4–6.

Discussion and Conclusion: A link between joint hyper-mobility and musculoskeletal symptoms has been demonstrated in adults. There is also some evidence that hypermobile children are more likely to experience musculoskeletal pain, particularly articular, but the extent to which joint hypermobility is related to growing pains specifically has been poorly defined. We have investigated a selective population of children with growing pains and have shown them to be significantly more hypermobile than the control children. The aetiology of growing pains remains unclear. While the growing pains will get better, in view of the possible association of joint hypermobility and other musculoskeletal complains, these children should be carefully assessed for joint laxity.

Flexion contracture in total knee arthroplasty (TKA) remains a challenge. Soft tissue management and additional bone resection are traditional options for flexion contracture correction. Our hypothesis was that the post implant computer aided measurements would not be significantly different to the extension angles measured at six weeks post-operatively in the follow-up clinic.

One hundred continuous TKA were performed by a single consultant using the OrthoPilot^® (BBraun, Aesculap) navigation system and Columbus implants. Of the group, 45 were male and 55 were female. Average age was 68 (range 49–87), mean BMI was 32.86 (22.26–51.86) and mean Oxford score preoperatively was 42 (range 21–56) and post-operatively 28 (range15–50). Data recorded at the preoperative assessment clinic included clinical flexion contracture and Oxford scores. Intra-operatively data were recorded using the navigation system. These included pre-operative flexion and extension angles, actual bone cuts of tibia and femur (both medial and lateral), postoperative correction of flexion and extension angles and soft tissue releases. At six weeks post operation, patients were seen in the follow clinic and clinical flexion contracture and Oxford score reassessed by the Arthroplasty outcome service.

Measurements were grouped and comparisons were made using a Pearson Chi-square test. There was no relationship between post-implant extension angle measurements (by computer) and extension angles at six weeks (by goniometer) (p=0.682). Also, there was no relationship between pre-operative measurement angles collected at the pre-assessment (by goniometer) and the pre-implant angles measured on the table (by computer) (p=0.682). We found that BMI (up to 35) and postoperative Oxford scores were significantly related to the extension levels with values of (p=0.008) and (p=0.027) respectively. Pre-operative Oxford scores, pre-operative extension, amount of bony resection and soft-tissue releases did not show any significant relationship with the post-operative extension obtained at six weeks.

The conclusions that we draw from this study are that there might be other factors that are likely to influence extension lag between the operation and the follow-up at six weeks. One of the factors that we could identify was the BMI. Attention to extensor lag is important because it leads to a poorer knee function, as indicated by the Oxford scores. Despite most of the post-implant measurement angles showing no extensor lag, about 20% of our patients still had more than five degrees flexion contracture at six weeks.

There is theoretical concern that volar plating has a disadvantage in cantilever bending when axially loaded dorsal to the neutral axis. This has implications for postoperative rehabilitation protocols and overall outcomes related to maintenance of reduction. Most recent biomechanical studies have compared volar locking plates to traditional dorsal non-locked plates. The purpose of this study was to compare the biomechanical stability of volar and dorsal locking plate fixation in a model of dorsally unstable distal radius fractures.

Fourteen synthetic composite radii (Pacific Research Laboratories, Vashon, WA) were used for this study. A dorsally unstable, extra-articular distal radius fracture was simulated by creating a dorsal wedge-shaped defect in the distal metaphysis. Half of the specimens were plated dorsally (n=7) while the other half were plated volarly (n=7) with 2.4mm distal radius locking T-plates (Synthes, Canada). Each specimen was loaded axially in five different positions: central (along the neutral axis of the radius) as well as dorsal, volar, radial and ulnar to the neutral axis using a MTS Sintech 1/G materials testing machine (MTS Systems, Eden Prairie, MN). The plated radii were loaded to 100 N in each position simulating physiological loading during normal range of motion. The main outcome measure was construct stiffness of the plate-bone system (slope of load-displacement curve) for all five loading positions.

Construct stiffness with dorsal locking plates was seven times greater than volar locking plates when dorsally loaded (p < 0.001), 60% greater when centrally loaded (p = 0.055) and 35% greater when volarly loaded (p = 0.029). There was no significant difference in stiffness with any other loading configurations.

The stability of dorsal locking plate fixation is superior to volar locking plate fixation in the setting of large dorsal defects in the distal radius. This is applicable to both fractures with dorsal comminution and dorsal opening-wedge distal radial osteotomies. Further clinical investigation is needed to compare functional outcomes and complication rates between modern dorsal and volar locking plate techniques.

Two of the major complications of total hip and knee arthroplasty is periprosthetic infection and aseptic loosening. The serum marker Procalcitonin (PCT) has been shown to be a sensitive indicator of bacterial infection, but very little is known of its behaviour in Orthopaedic practice. The diagnosis of periprosthetic infection still remains a difficult diagnosis.

A prospective study over 6 months of 59 patients undergoing either primary total hip or knee arthroplasty was performed, which included 32 hips. The mean age was 70 years. There were no exclusion criteria. Serum blood samples for PCT, CRP, ESR and WCC were taken pre- operatively and on days 1, 3 and 5 post- operatively. Patient records were reviewed after their routine 6 week follow- up. There was no clinical suspicion of infection at this stage, or during their hospital stay.

Fifty patients (85%) had PCT concentrations within the normal range (< 0.5ng/ml) on all 4 days, and only 5 recorded a value > 1.0ng/ml. Only 1 patient had an elevated level on day 5. The other markers all showed sporadic elevation over the 3 post- operative days

The usefulness of PCT in diagnosing surgical infection has been frequently researched in cardio- thoracic and abdominal surgery. However, there is debate as to what cut- off value should represent infection, ranging from 1– 10ng/ml. This is largely because the natural acute phase response caused by these operations elevates PCT levels. This study convincingly shows that PCT, unlike the routine inflammatory markers, is not significantly stimulated by primary hip and knee arthroplasty. This would imply that PCT may be useful in diagnosing periprosthetic infection. A large multicentre study involving patients undergoing revision surgery would help validate this assumption.

Our cadaveric biomechanical study has demonstrated evidence to suggest that commercially available removable cast boots do provide the same reduction of force on a first MTP joint arthrodesis site, during the early post operative period, as a traditional fiberglass cast.

This study compares the effectiveness of three common models of walking boots to a fiberglass cast in protecting an arthrodesis of the first metatarsophalangeal (MTP) joint in the early post-operative period.

First MTP joint arthrodesis is commonly performed for various clinical problems. Weight bearing is encouraged post operatively, however the arthrodesis site must be protected from excessive forces until bony union is achieved.

Two cadaveric models of a 1^st MTP joint arthrodesis were prepared with a strain gauge placed at the joint, which provided a measure of the bending moment across the fusion site. Walking was simulated by applying a force to the sole of the cadaver foot at multiple positions, from the heel to the toe, representing the stages of gait from heel strike to toe off. Loading trials were performed using each of the walking boots and a fiberglass cast, with the moments across the joint compared.

For both specimens, the “Walkabout” by Smith & Nephew had the lowest mean moment. Specimen one showed that the “Walkabout” and “Sampson Walker” were both better than the “Equalizer” and fiberglass cast (p< 0.05). Specimen two showed that the “Walk-about” was better than all others (P< 0.05). Also, for both specimens, the “Walkabout” by Smith & Nephew had the smallest absolute maximum moment (P< 0.05). Our study has shown that removable cast boots do provide the same, if not more, reduction of force on a first MTP joint arthrodesis site as a traditional cast.

Introduction: Over the past decade metal-on-metal bearings in the form of hip resurfacings have been increasing in popularity and with it, an associated interest in the potential side effects of elevated serum metal ion levels.

Method: We prospectively measured the cobalt and chromium serum levels of 20 patients over a two-year period following Birmingham hip resurfacing. Cobalt was measured with inductively coupled plasma mass spectrometry and chromium using graphite furnace atomic absorption spectrometry.

Results: For serum cobalt there was an initial increase, to a peak at six months then a gradual decline. A similar pattern was observed for chromium, although the peak occurred slightly later at nine months.

Conclusion: One-off single measurements of metallic ion levels is of minimal clinical use, when the actual pattern of ion elevation and fall is not known. This study allows us to expect a peak at certain times following a hip resurfacing and a gradual decline thereafter.

Introduction and Aims: Hip resurfacing has undergone a resurgence of interest in the past five years, requiring surgeons to learn new principles and new operative techniques. For experienced surgeons, the learning curve is more transparent than in their earlier careers.

Method: We have reviewed the first 100 hip resurfacings performed by two experienced surgeons. Results of the first 20 and second 20 were compared for a difference, then the first 30 and second 30 and finally the first 50 and second 50. We evaluated accuracy of pre-operative planning to final sizing, pre-operative neck shaft angle and post-operative prosthesis angle, revision rates, complication rates, equipment problems, placement of the acetabular component.

Results: On comparing the first 50 procedures performed with the second 50 performed, there was a significant difference (p< 0.001) in positioning of the femoral prosthesis, notching of the femoral neck, seating of the femoral and acetabular component position and seating. When comparing the first 20 and second 20 procedures no significant difference was noted.

Conclusion: We note there is a definite learning curve associated with the hip resurfacing procedure and it was longer than we estimated.

Introduction: Over the past decade metal on metal bearings in the form of hip resurfacings have been increasing in popularity and with it an associated interest in the potential side effets of elevated serum metal ion levels.

Methods: We prospectively measured the cobalt and chromium serum levels of 20 patients over a 2 year period following Birmingham hip resurfacing. Cobalt was measured with inductively coupled plasma mass spectrometry and chromium using graphite furnace atomic absorption spectrometry.

Results: For serum cobalt there was an initial increase to a peak at 6 months then a gradual decline. A similar pattern was observed for chromium, although the peak occurred slightly later at 9 months.

Conclusions: One off single measurements of metallic ion levels are of minimal clinical use, when the actual pattern of ion elevation and fall is not known. This study allows us to expect a peak at certain times following a hip resurfacing and a gradual decline thereafter.

We describe our early experience with the implantation of the first consecutive 231 primary Birmingham Hip resurfacings. At a mean follow up of 33 months, survivorship was 99.14 %, with revision in one patient for a loose acetabular component and one unrelated death.

Mean Harris Hip score improved from a mean of 62.54 ( Range : 8–92) to 97.74. (Range: 61 – 100) Mean flexion improved from a mean of 91.52°, ( Range : 25° –140°) to a mean 110.41°. ( Range : 80° – 145°)

1 patient presented at 6 weeks post resurfacing with pain and no history of trauma. An undisplaced fracture of the superior femoral neck was seen, which healed with a period of non-weight bearing.

96.94% of patients rated their prosthesis as good / excellent, the remainder rated it good/fair.

220 consecutive hip resurfacing procedures were reviewed at a minimum of two years follow up to assess the incidence of heterotopic ossification and its effect on function and clinical outcome. We also reviewed the pre-operative diagnosis, gender and previous surgery. The overall percentage of heterotopic ossification was 58.63%. The incidence of Brooker 1 was 37.27%, Brooker 2 was 13.18% and Brooker 3 was 8.18%.

Male osteoarthritics had the highest incidence of heterotopic bone formation. Three males underwent excision of heterotopic bone, two for pain and stiffness and one for decreased range of movement.

Both antero-posterior and lateral radiographs were reviewed for evidence of heterotopic bone formation. 12.7% had no evidence of heterotopic bone formation on one view but clearly had on the second view.

Overall we found no evidence that heterotopic bone formation affected the clinical or functional outcome of the hip resurfacing at a mean of 3 years follow up.

Introduction: Hip resurfacing has undergone a resurgence of interest in the past 5 years. This has required the acquistion of new surgical principles and techniques. Allowing us to study the learning curve associated with acquiring these skills.

Methods: The first 50 hip resurfacings and the second hip resurfacings performed by two consultant surgeons were compared for femoral fit, pre-operative femoral neck shaft angle, post-operative prosthesis angle, acetabular cup abduction angle, seating of the acetabular component, post-operative complications and revision rates.

Results: There was a statistically significant improvement in the alignment of acetabular components, seating of the acetbaular component and fewer problems associated with the acetabular introducer in the second cohort. There was more consistent placement of the femoral prosthesis in the neck,less notching and less variation in position in the second cohort.

Conclusions: There is a definite leaning curve associated with hip resurfacing and it was longer than expected.

A prospective consecutive series of uncemented, hydroxyapatite coated primary hip replacements utilizing two different types of alumina ceramic inserts and alumina ceramic heads is reported. Clinical and radiological results together with complications and reoperations are detailed.

193 hips followed up to 39 months using the Secur fit cup with ABC liner (Stryker). 40 hips using the Trident AD shell with the Trident titanium wrapped liner are reported up to 18 months.

Clinical scores (Harris and Postel Merle D’Aubigne) are similar to metal polyethylene at early review. SF 12 physical scores improved post operation. 100% bony ingrowth was seen radiologically (Engh and ARA scores).

Liner rim surface chips on insertion were seen in 1.4% of the ABC liners and none occurred after the 20th hip. No chips were seen in the Trident liners. One ABC liner sustained extensive surface rim chips in a heavy fall at 24 months. This is the first report of such a liner fracture. One Secur fit ABC cup was revised for recurrent subluxation.

The importance of early revision of ceramic fractures and the re use of shells is discussed. The addition of a titanium sandwich wrap to the ceramic liner is likely to eliminate the early chips.