INTRODUCTION

Cementless femoral component designs supplemented with hydroxyapatite (HA) coating have been hypothesised to enhance osseointegration, thereby improving stability and clinical outcomes. We herein offer interim results at 5 years from a prospective, multi-centre study of a femoral stem (SL-PLUS™ Hip Stem Prosthesis), forged from titanium alloy (Ti6Al7Nb) and consisting of a titanium plasma sprayed coating (0.3mm) with an additional 0.05mm layer of HA.

Aim

Bumps and lumps of the hand are a common cause for consultation in general practice. However not all of these lesions are of true neoplastic nature and malignant tumours are a rarity in this location.

Introduction: Tumours of the foot are rare, representing only 4 to 8 per cent of all bone and soft tissue tumours: a negligible number compared to degenerative, posttraumatic, vascular and metabolic diseases of this exposed region. Hence neoplasms of the foot are often diagnosed late and treated inadequately.

Methods: The records of all tumours of the foot and ankle treated surgically at our institution in the period 1993 to 2007 were reviewed. Because of their non-neoplastic nature typical lesions of the foot such as plantar fibromatosis or Morton neuroma as well as ganglion and the like were not included in this study. History, location, radiographic and clinical findings were analysed, malignant tumours were followed up by X-ray and MRI.

Results: Of the eighty-eight cases which were further investigated, there were forty-four bone tumours and forty-four neoplastic soft tissue lesions. Sixty-nine cases (78%) were benign tumours, half of them (35 cases) located in the bone and in the soft tissue (34 cases) respectively. There were forty-four male and female patients each, the mean age being 40 years (range 4 to 85) for all cases, 39 years for benign and 45 years for malign tumours respectively.

There were nineteen malignant lesions, nine of which were bone tumours; the most common being chondrosarcoma (3) and osteosarcoma (3). Malignant soft tissue tumours (10) were very heterogeneous, clear cell sarcoma being the only tumour appearing at least twice.

Out of thirty-four benign soft tissue tumours, pigmented villonodular synovitis (11), fibrous (9) and lipomatous (5) tumours have been the most frequent. Thirty five benign bone tumours included chondroma (10), solitary bone cyst (10), aneurysmatic bone cyst (3), osteoid-osteoma (3) and giant cell tumour (3).

Conclusion: Knowledge of tumour prevalence under consideration of the patient’s age and location of the tumour is an important prerequisite for identifying neoplastic lesions of the foot.

Introduction: The treatment of symptomatic rotator cuff rupture is a common therapeutic challenge in our ageing population with high functional demands. We reviewed our results of arthroscopic treatment (introduced in our department in October 2005) and compared the outcome with that of open repair.

Material and Methods: The 73 patients of the open group were operated between October 1998 and October 2006. Treatment consisted of classic open repair done by a parasagital incision with transosseous sutures in 69 and titanium anchors in 4 cases. All patients were immobilised in an abduction splint for 6 weeks and only passive exercises were performed during this period. Strengthening exercises were allowed after 3 month. The arthroscopic group included 30 patients operated between October 2005 and June 2008. A single row repair using 1–3 titanium anchors was performed via 3 to 5 incisions. The abduction splint was used for 4 weeks and strengthening exercises were allowed after 2 month. Standard x-rays in 3 planes were performed praeop, postop and at the latest follow up examination. A praeop MRI was done in all cases. Clinical examination used the non age adapted Constant score and complications were recorded.

Results: Follow up was possible for 29 men and 36 women with a mean age of 57 years (35 to 78) in the open versus 15 men and 13 women with a mean age of 59 years (44 to 74) in the arthroscopic group. Mean follow up averaged 36 month (3–102) in the open and 15 month (3–35) in the arthroscopic group. One tendon was affected in 45% versus 75%, two tendons in 45% versus 25% and three tendons in 10% versus 0% in the open and arthroscopic groups. The mean Constant score could be improved from 50 (29–68) praeop to 71 (39–97) postop in the open and 52 (28–62) praeop to 80 (45–98) postop in the arthroscopic group. If only one and two tendon ruptures were recorded in the open group the mean postop Constant score was 76. Four complications were encountered in the open group. One patient had to be revised due to deep infection and one because of wound healing problems. Two cases of frozen shoulder could be managed conservatively. In the arthroscopic group one patient showed a temporal irritation of the ulnar nerve and another a frozen shoulder. Both cases could be managed conservatively.

Conclusion: Short to mid term results showed no difference in clinical outcome comparing open and arthroscopic procedures. The higher mean postop Constant score of the arthroscopic group was mainly due to the lager tears sizes of the open group. Advantages of the arthroscopic procedure are the possibility of faster rehabilitation and that the operation seems less prone to infection and wound healing problems.

Introduction: Revision surgery for stem loosening and peri-implant bone loss of variable extent is a major challenge for orthopedic surgeons. Our strategy has been to use cementless straight stems of rectangular cross-section for revisions. To ascertain the value of this implant we analyzed the results at a minimum follow-up of 10 years.

Material and Method: Between October 1991 and end 1998, 125 patients (134 hips) underwent revision surgery. Of these, 39 were males and 86 were females. Sixty-seven of the original implants were cemented and as many were cementless. Cementless revision stems (SLR; Plus Orthopedics, Aarau, Switzerland) size 3 to 11 (180 to 223 mm in length) were used for revisions. Patient age at the time of surgery was 37.8 to 89.3 (mean, 71.0) years.

Fifty patients (53 hips) died post revision 0.0 to 13.5 (mean, 6.8) years. Their implants had been followed-up radiographically for 0.0 to 9.2 (mean, 3.6) years. At the time of revision these patients had been 48.9 to 89.3 (mean, 76.7) years old. One of them had undergone stem revision for aseptic loosening one year post surgery. Another 6 were revised 1.4 to 13.9 years post surgery, 5 for low grade infection and 1 for peri-implant fracture.

Seven patients refused to present for follow-up because of advanced age and poor cooperation. Eight were contacted by telephone. These 15 patients were not re-operated. Five patients were altogether lost to follow-up, thus leaving a total of 53 hips (49 patients) for analysis at a follow-up time of at least 10 years. The follow-up time was 10.0 to 16.1 (mean, 11.6) years.

For radiographic follow-ups monitor-guided a.-p. and axial radiographs were recorded. These were analyzed by Gruen zones.

Results: All stems were properly aligned along the long femoral axis, except in 1 patient, who had sustained a peri-implant fracture during a fall with axial stem subsidence responding to conservative treatment. In 38 patients peri-implant bone apposition was detected in all 7 Gruen zones. This was combined with bone resorption in other zones in 2 patients. Four patients presented with osteolytic lesions. In one of them with metal-on-metal articulating surfaces, the lesion extended to several segments and will necessitate revision. All other stems were stable. None of them was at risk.

Conclusion: This analysis showed that the SLR revision stem performs well for an intermediate follow-up time of at least 10 years.

Introduction: Loosening of the acetabular Implant after Total Hip Replacement (THR) is often associated with massive bone loss. Many different solutions to this problem have been reported. The implant we used in our series is a cementless cup that consists of two different modular components: the outer shell, with a caudal hook and 3 iliac wings, and the inner module that can be placed in 20° angulation, where the liner is inserted. Non-structural bone graft was used.

Materials and Methods: From April 2002 to October 2004 24 patients were treated with this implant (age 70,7 years, 48–88). They had had zero to six prior surgeries. Indications were: Aseptic loosening (20), septic loosening (2), repetitive luxations(1), intraoperative acetabular fracture (1). Acetabular bone loss was intraoperatively graded using the DGOT classification. Paprosky Classification was used for preoperative radiological grading.

Harris Hip Score (HHS) was used for clinical evaluation (preoperative scores were retrospectively ascertained from patients’ charts). For radiological follow up plain X-rays of the pelvis a.p. and targeted views of the cup were used. Radiolucency, osteolysis (around cup, caudal hook, screws), migration (medial, cranial) and dumping was noted and the results divided into 3 groups: stable (no migration) at risk (cranial or medial migr.), loosened (cranial and medial migr.).

Results:18 Patients with implants in situ could be examined at an average follow up time of 18,3 months (3–30). (1died, 1 could not be reached, 2 did not want to come to fu, 2 explantations after infection). Average stay in hospital: 26 days, non weight bearing for av.: 9,8 weeks. Complications: 1 transient common peroneal nerve palsy, 1 luxation after 4 months (treated conservatively).

HHS improved from 36,4 to 69,3 points (max. 100). Pain: 15,5 to 36,8 pts (max. 44). Activity of daily living:14,3 to 36,8pts (max. 47). Walking distance 3,6–5,8 pts (max.11).

Radiological results (n=19, patient who died included in rad. FU): Radiolucency and osteolysis: Cup 5, hook 12, screws 10. Migration: medial:7 (all of those had medial bone defects), cranial:4, angulation > 4°:4 Outcome: stable: 11, at risk: 3, loosened 5 (1 died, 1 explanted, 3 control every 3 months)

Conclusion: In our series the SPH Bicomponente does not provide sufficient postoperative stability to facilitate good ingrowth of bone graft. Loosening occurs especially in cases with medial bone defects where the cup has too little contact to pelvic bone. In these cases cemented cups or structural grafts might give better stability. ‘At risk’ patients show better clinical performance than one would expect from the radiological findings.

A second follow up is starting recently with an average FU time of about 36 months.

Aims: Kinematic and pointing procedures, are used for non-image based navigated implantation of TKA. Pointing procedures require exact knowledge about the landmarks. In this anatomical study, landmarks are defined and repeatedly referenced. The precision and the reproducibility are evaluated, by means of inter- and intra- observer study. Using the landmarks, the axes of the femur and tibia are calculated. Methods: The specific landmarks of 30 femur and 27 tibia specimens, were palpated by 3 surgeons and digitised by means of a photogrammetric system, as used intra-operatively. The recorded data are evaluated. Results: The specific landmarks can be referenced with great precision. The vectors that influence the implant position, show femoral a mean inter-observer deviation of 0,9mm and 1,0mm tibial. The repeating accuracy of every single observer was 1,5mm femoral and 1,0mm tibial. The calculated long axes at the femur and tibia, thus reach a precision of 0.1° (min-max:0°–0,9°) at the femur and 0,2° (min-max:0°–1,1°) at the tibia. The short axes at the distal femur and at the proximal tibia, exhibit an average deviation of 0,7° to 1,9° (min-max: 0°–11,3°). Conclusion: Long axes (mechanical axes) can be determined exactly, the precision of the short axes (rotational axes) is unsatisfactory, although palpation of landmarks were accurate. Therefore, palpation of more than one rotational axis at the femur and the tibia, is mandatory and should be visualized on the monitor during the operation.

Aims: The aim of this prospective study was to analyse the Ludloff osteotomy for its potential of correcting hallux valgus deformity. Methods: Between September 1998 and October 1999 84 consecutive patients who underwent a Ludloff osteotomy were included in this prospective study. All patients were examined preoper-atively and at a minimum follow up of 2 years according a standardized questionnaire based on the HMIS of the American Foot and Ankle Society. X-rays were taken preoperatively, at 6 weeks and at þnal follow up. Results: 75 patients were available for an average follow up of 33 months (24 to 41). The average preoperative HMIS was 52 points and at follow up 87 points. 78% of the patients rated the outcome as excellent and good. 82% of patients were painfree at follow up. Radiological evaluation revealed a preoperative average hallux valgus angle (HV) of 36û and a preoperative average intermetatarsal angle (IM) of 17û This was corrected by surgery to an average HV of 14û and an average IM of 8û. Preoperatively sesamoidposition Grade III was present I 71%, Garde II in 29%. At follow up Grade 0 was present in 60%m Grade 1 in 37% and Grade2 in 3%. There was no Grade 3 sesamoid position at follow up. Conclusions: The ludloff osteotomy is a good alternative for the correction of severe hallux valgus deformity. In elderly patients and osteoporotic bone early weight-bearing should not be allowed because of poor bone quality.

Aims: The mini-robot-supported ligament balancing technique of the Galileo navigation system is described “step by step”. Methods: The aim of an optimal ligament balancing is a symmetrical ligament tension as well as flexion and extension gaps which are equal and right-angled. This is reached with the Galileo system through: 1) Robot controlled shifting of the resection block in anterior-posterior and/or proximal-distal direction. 2) Use of an instrumented ligament spreader which measures force and joint gap. The flexion gap measurement is conveyed to the computer which calculates the optimal proximal-distal position of the implant. Then the robot-controlled resection block is positioned accordingly. Results: Surgical Technique: The tibial and the posterior femoral resections are carried out first. The spreader is then inserted into the flexion gap with a ligament tension of 100N for both, medial and lateral condyle. The polyethylene thickness is chosen assuming a right-angled configuration (same gap medial and lateral) and reported to the computer. Then the spreader is inserted into the extension gap, aligned to the axis and a ligament tension of 100 Newton is applied. Should the extension gap not be right-angled, corresponding soft tissue releases have to be performed. The medial and lateral extension gap is entered into the computer which calculates the optimal implant position and positions the robotcontrolled resection block. The resection is performed with a conventional bone saw. Conclusions: Galileo is a practice oriented navigation system for TKR with integrated mini-robot. The resection block positioning in 0,5 mm steps in anterior-posterior and proximal-distal direction enables optimal ligament balancing. The combination of ligament spreader and navigation results in perfect ligament balancing and reconstruction of the mechanical axis even with large axis deviations and pathological ligament deformations.