Modern athletes are constantly susceptible to performance-threatening injury as they push their bodies to greater limits and endure higher physical stresses. Loss of performance and training time can adversely and permanently affect a sportsperson’s career. Now more than ever with advancing medical technology the answer may lie in biologic therapy. We have been using peripheral blood stem cells (PBSC) clinically and have been able to demonstrate that stem cells differentiate into target cells to enable regenerative repair. The potential of this technique as a regenerative agent can be seen in three broad applications: 1) articular cartilage, 2) bone and 3) soft tissue. This article highlights the successful cases, among many, in all three of these applications.

The February 2013 Knee Roundup³⁶⁰ looks at: mobile-bearing TKRs; arthroscopic ACL reconstruction; the use of chondrocytes for osteochondral defects; ACL reconstruction and the return to pivoting sports; ACLs and the MOON study; the benefit of knee navigation; and trabecular metal.

The purpose of this study was to measure the radiological parameters of femoral component alignment of the Oxford Phase 3 unicompartmental knee replacement (UKR), and evaluate their effect on clinical outcome. Multiple regression analysis was used to examine the relative contributions of the radiological assessment of femoral component alignment in 189 consecutive UKRs performed by a single surgeon. The American Knee Society scores were compared between groups, defined as being within or outside recommended tolerances of the position of the femoral component. For the flexion/extension position 21 UKRs (11.1%) lay outside the recommended limits, and for posterior overhang of the femoral component nine (4.8%) lay outside the range. The pre-operative hip/knee/ankle (HKA) angle, narrowest canal distance from the distal femoral entry point of the alignment jig and coronal entry-point position had significant effects on the flexion/extension position. Pre-operative HKA angle had a significant influence on posterior overhang of the femoral component. However, there was no significant difference in American Knee Society scores relative to the position of the femoral component.

Excision of a physeal bar and filling the space with interposition material may allow resumption of normal growth. Both the extent and the location of the bar and the amount of growth remaining from physis must be determined. Computer-assisted surgery is being used increasingly in various fields of orthopaedics. We describe the management of a patient with premature physeal arrest of the right distal tibia in which resection of a physeal bar was achieved under real-time three-dimensional intra-operative monitoring by computer-assisted navigation.

The advantage of this method over other means of imaging is that intra-operative identification can increase the accuracy of resection of the bar.

Limb salvage involving wide resection and reconstruction is now well established for managing musculoskeletal sarcomas. However, involvement of major nerves and vessels with a large volume of muscle and skin may result in a useless limb, contributing to depression and a low quality of life. We have been studying alternative treatments for musculoskeletal sarcoma since 1990, and have recently established a regime using photodynamic surgery with cells labelled with acridine orange, photodynamic therapy with cells treated similarly and radiodynamic treatment using the effect of X-rays on such cells.

These techniques have been used after marginal or intralesional resection of tumours since 1999 and have enabled maintenance of excellent limb function in patients with sarcomas.

There are three basic concepts that are important to the biomechanics of pedicle screw-based instrumentation. First, the outer diameter of the screw determines pullout strength, while the inner diameter determines fatigue strength. Secondly, when inserting a pedicle screw, the dorsal cortex of the spine should not be violated and the screws on each side should converge and be of good length. Thirdly, fixation can be augmented in cases of severe osteoporosis or revision.

A trajectory parallel or caudal to the superior endplate can minimise breakage of the screw from repeated axial loading. Straight insertion of the pedicle screw in the mid-sagittal plane provides the strongest stability.

Rotational stability can be improved by adding transverse connectors. The indications for their use include anterior column instability, and the correction of rotational deformity.

Guiding growth by harnessing the ability of growing bone to undergo plastic deformation is one of the oldest orthopaedic principles. Correction of deformity remains a major part of the workload for paediatric orthopaedic surgeons and recently, along with developments in limb reconstruction and computer-directed frame correction, there has been renewed interest in surgical methods of physeal manipulation or ‘guided growth’. Manipulating natural bone growth to correct a deformity is appealing, as it allows gradual correction by non- or minimally invasive methods.

This paper reviews the techniques employed for guided growth in current orthopaedic practice, including the basic science and recent advances underlying mechanical physeal manipulation of both healthy and pathological physes.

A total of 80 patients with an acute rupture of tendo Achillis were randomised to operative repair using an open technique (39 patients) or non-operative treatment in a cast (41 patients). Patients were followed up for one year. Outcome measures included clinical complications, range of movement of the ankle, the Short Musculoskeletal Function Assessment (SMFA), and muscle function dynamometry evaluating dorsiflexion and plantar flexion of the ankle. The primary outcome measure was muscle dynamometry.

Re-rupture occurred in two of 37 patients (5%) in the operative group and four of 39 (10%) in the non-operative group, which was not statistically significant (p = 0.68). There was a slightly greater range of plantar flexion and dorsiflexion of the ankle in the operative group at three months which was not statistically significant, but at four and six months the range of dorsiflexion was better in the non-operative group, although this did not reach statistically significance either. After 12 weeks the peak torque difference of plantar flexion compared with the normal side was less in the operative than the non-operative group (47% vs 61%, respectively, p < 0.005). The difference declined to 26% and 30% at 26 weeks and 20% and 25% at 52 weeks, respectively. The difference in dorsiflexion peak torque from the normal side was less than 10% by 26 weeks in both groups, with no significant differences. The mean SMFA scores were significantly better in the operative group than the non-operative group at three months (15 vs 20, respectively, p < 0.03). No significant differences were observed after this, and at one year the scores were similar in both groups.

We were unable to show a convincing functional benefit from surgery for patients with an acute rupture of the tendo Achillis compared with conservative treatment in plaster.

This prospective study describes the outcome of the first 1000 phase 3 Oxford medial unicompartmental knee replacements (UKRs) implanted using a minimally invasive surgical approach for the recommended indications by two surgeons and followed up independently. The mean follow-up was 5.6 years (1 to 11) with 547 knees having a minimum follow-up of five years. At five years their mean Oxford knee score was 41.3 (sd 7.2), the mean American Knee Society Objective Score 86.4 (sd 13.4), mean American Knee Society Functional Score 86.1 (sd 16.6), mean Tegner activity score 2.8 (sd 1.1). For the entire cohort, the mean maximum flexion was 130° at the time of final review.

The incidence of implant-related re-operations was 2.9%; of these 29 re-operations two were revisions requiring revision knee replacement components with stems and wedges, 17 were conversions to a primary total knee replacement, six were open reductions for dislocation of the bearing, three were secondary lateral UKRs and one was revision of a tibial component. The most common reason for further surgical intervention was progression of arthritis in the lateral compartment (0.9%), followed by dislocation of the bearing (0.6%) and revision for unexplained pain (0.6%). If all implant-related re-operations are considered failures, the ten-year survival rate was 96% (95% confidence interval, 92.5 to 99.5). If only revisions requiring revision components are considered failures the ten-year survival rate is 99.8% (confidence interval 99 to 100).

This is the largest published series of UKRs implanted through a minimally invasive surgical approach and with ten-year survival data. The survival rates are similar to those obtained with a standard open approach whereas the function is better. This demonstrates the effectiveness and safety of a minimally invasive surgical approach for implanting the Oxford UKR.

Open reduction and internal fixation of high-energy pilon fractures are often associated with serious complications. Various methods have been used to treat these injuries, with variable results. A total of 17 consecutive patients with pilon fractures of AO/OTA type 43-B3 (n = 1), type C2 (n = 12) and type C3 (n = 4) were treated by indirect reduction by capsuloligamentotaxis and stabilisation using an ankle-spanning Ilizarov fixator. The calcaneal ring was removed at a mean of 3.7 weeks (3 to 6). A total of 16 patients were available for follow-up at a mean of 29 months (23 to 43). The mean time to healing was 15.8 weeks (13 to 23). Nine patients had pin-track infections but none had deep infection or osteomyelitis. Four patients (25%) had malunion. Fair, good or excellent ankle scores were found in 14 patients. External fixation with a ring fixator achieves stable reduction of the fractured fragments without additional trauma to soft tissues.

With minimum complications and good healing results, the Ilizarov apparatus is particularly useful for high-energy pilon fractures.

We retrospectively reviewed 35 cemented unicompartmental knee replacements performed for medial unicompartmental osteoarthritis of the knee in 31 patients ≤50 years old (mean 46, 31 to 49). Patients were assessed clinically and radiologically using the Knee Society scores at a mean follow-up of 9.7 years (5 to 16) and survival at 12 years was calculated. The mean Knee Society Function Score improved from 54 points (25 to 64) pre-operatively to 89 (80 to 100) post-operatively (p < 0.0001). Six knees required revision, four for polyethylene wear treated with an isolated exchange of the tibial insert, one for aseptic loosening and one for progression of osteoarthritis.

The 12-year survival according to Kaplan-Meier was 80.6% with revision for any reason as the endpoint. Despite encouraging clinical results, polyethylene wear remains a major concern affecting the survival of unicompartmental knee replacement in patients younger than 50.

We performed a prospective, randomised study to compare the results and rates of complications of primary total knee replacement performed using a quadriceps-sparing technique or a standard arthrotomy in 120 patients who had bilateral total knee replacements carried out under the same anaesthetic. The clinical results, pain scales, surgical and hospital data, post-operative complications and radiological results were compared.

No significant differences were found between the two groups with respect to the blood loss, knee score, function score, pain scale, range of movement or radiological findings. In contrast, the operating time (p = 0.0001) and the tourniquet time (p < 0.0001) were significantly longer in the quadriceps-sparing group, as was the rate of complications (p = 0.0468).

We therefore recommend the use of a standard arthrotomy with the shortest possible skin incision for total knee replacement.

Previous studies on the anatomy of the lumbar spine have not clarified the precise relationship of the origin of the lumbar roots to their corresponding discs or their angulation to the dural sac. We studied 33 cadavers (25 formalin-preserved and eight fresh-frozen) and their radiographs to determine these details.

All cadavers showed a gradual decrease in the angle of the nerve root from L1 to S1. The origin of the root was found to be below the corresponding disc for the L1 to L4 roots. In the formalin-preserved cadavers 8% of the L5 roots originated above, 64% below and 28% at the L4/L5 disc. In the fresh cadavers the values were 12.5%, 62.5% and 25%, respectively. For the S1 root 76% originated above and 24% at the L5-S1 disc in the formalin-preserved cadavers and 75% and 25%, respectively, in the fresh cadavers.

A herniated disc usually compresses the root before division of the root sleeve. Thus, compression of the thecal sac before the origin of the root sleeve is common for L1 to L5 whereas compression at the root sleeve is common for S1.

Our findings are of value in understanding the pathophysiology of prolapse of the disc and in preventing complications during surgery.