The Caledonian Technique ^TM has been widely accepted as a safe and effective way of improving post-operative recovery and reducing length of stay following total knee arthroplasty. In keeping with the principles of the enhanced recovery programme its use has slowly spread from specialised units into district general hospitals. There is little evidence using PROMs that supports the use of the Caledonian Technique in the DGH setting. The primary aim of this study was to find out whether the Caledonian Technique was being successfully implemented in this district general setting for TKA. The secondary aim was to identify whether there was a difference in the patients’ perspectives of success post discharge.

This is a prospective questionnaire-based cohort study of patients undergoing total elective TKA in this DGH. It was carried out at Forth Valley Royal Hospital, Larbert, Scotland between June 2011 and 2012. All patients undergoing elective TKA were asked to complete a questionnaire assessing pain, mobilisation, function and satisfaction at 6 weeks post-operatively. Case notes of all returned questionnaires were reviewed and surgeon, protocol followed (Caledonian or non-Caledonian), length of stay, analgesic requirements, discharge analgesia and complications recorded.

We have shown that length of stay, analgesic requirement and cost were all less in the Caledonian group (n=17) compared to non-Caledonian (n=17). In addition there were statistically significant increases in patients mobilising on day 1 and achieving opiate free discharge in the Caledonian group. Patient satisfaction was higher in 11 out of 12 PROMs post discharge.

This confirms that previously shown improvements in length of stay and early mobilisation seen in specialised units can also be achieved in the DGH setting. Secondly it also shows that there is no negative impact on patient satisfaction and outcomes following early mobilisation and discharge.

Soft tissue balancing is critical to successful knee arthroplasty. Pre-operative planning ensures that the surgeon is prepared for any eventuality. We report a large femoral exostosis resulting in gross instability, requiring revision to a constrained implant.

An 81 year old female presented with osteoarthritis of the left knee. Xray showed a medial bony mass. CT noted a large bony exostosis arising from the posteromedial femoral condyle. Review showed the exostosis was not related to the medial collateral ligament (MCL). At surgery, the exostosis was noted to be tenting the MCL – excision resulted in complete flaccidity. A trial of the Biomet AGC prosthesis revealed gross medial instability. The decision was taken to convert to a DePuy Sigma TC3 system. Whilst removing TC3 trial components, a lateral condyle fracture occurred. This was fixed with a 1/3 tubular plate and interfragmentary screw. The TC3 system and an AGC patellar button were found to be congruent. A small lateral release was performed, the deep MCL was replaced with tagging sutures through the MCL and the pes anserinus. At 9 weeks post operatively, the patient was pain free and mobilising independently. The knee was stable, with range of movement from 0 to 110 degrees.

To our knowledge, this is the first report of such a complication in the literature. It highlights that despite optimal preoperative planning, the surgeon must be prepared to adapt to the situation at hand. It also highlights the importance of having ‘bail out’ options available on shelf when performing routine surgery.

Post-operative regimes involving the use of intra-articular local anaesthetic infiltration may allow early mobilisation in patients undergoing total knee arthroplasty. Few studies have evaluated such regimes outside specialist arthroplasty units. We aimed to determine whether an enhanced recovery programme including the use of local anaesthetic administration could be adapted for use in a district general setting.

Following introduction of this regime to our unit, 100 consecutive patients undergoing primary total knee arthroplasty were reviewed. 56 patients underwent a standard analgesic regime involving a general or spinal anaesthetic and oral analgesics post operatively (group1). 48 patients underwent the newly introduced regime, which included pre-operative counselling, peri-articular local anaesthetic infiltration at operation and intra-articular local anaesthetic top-up administration post-operatively for 24 hours (group 2). Length of stay, post-operative analgesic requirements, and range of knee motion post-operatively were compared.

Median length of stay was less for patients in group 2 compared with those in group 1 (4 days compared to 5 days, p<0.05). Patients in group 2 required lower total doses of opiate analgesia post-operatively. 90% of patients in group 2 were ambulant on the first post operative day, compared with less than 25% of patients in group 1. Mean knee flexion on discharge was greater in patients in group 2 compared with those in group 1 (85 degrees compared with 75 degrees). No infective complications from intra-articular catheter placement were observed. However, technical difficulties were encountered during the introduction period, including loss of catheter placement, leakage of local anaesthetic and adaptation of nursing time for top-up anaesthetic administration.

A rehabilitation regime involving local anaesthetic infiltration for total knee arthroplasty can successfully be adapted for use in a district general setting. Our results suggest if initial technical difficulties are overcome, this regime can provide effective postoperative analgesia, early mobilisation and reduced hospital stay.

Trochlear dysplasia is an important anatomical abnormality in symptomatic patellar instability. Our study assessed the mismatch between the bone and cartilaginous morphology in patients with a dysplastic trochlea compared with a control group.

MRI scans of 25 knees in 23 patients with trochlear dysplasia and in 11 patients in a randomly selected control group were reviewed retrospectively, in order to assess the morphology of the cartilaginous and bony trochlea. Inter- and intra-observer error was assessed.

In the dysplastic group there were 15 women and 8 men with a mean age of 20.4 years (14 to 30). The mean bony sulcus angle was 167.9⁰ (141⁰ to 203⁰), whereas the mean cartilaginous sulcus angle was 186.5⁰ (152⁰ to 214⁰; p < 0.001). In 74 of 75 axial images (98.7%) the cartilaginous contour was different from the osseous contour on subjective assessment; the cartilage exacerbated the abnormality.

Our study shows that the morphology of the cartilaginous trochlea differs markedly from that of the underlying bony trochlea in patients with trochlear dysplasia. MRI is necessary in order to demonstrate the pathology and to facilitate surgical planning.

Introduction: This study assesses the prevalence of trochlear dysplasia as a cause of patello-femoral arthritis (PFOA), though for many years the condition was scarcely recognised and not recorded.

Method: Since 1989 385 primary isolated patello-femoral replacements have been performed in Bristol for patello-femoral arthritis.

The diagnoses recorded were:

Lateral facet PFOA 227

Symmetrical PFOA 95

Medial facet PFOA 24

Dislocation 15

Subluxation 33

Post traumatic 6

Trochlear dysplasia was noted either retrospectively or as “other diagnosis” in only 10 cases between 1989 and 2003, however in the last year, the condition became recognised locally, and has been recorded in 11 of the 48 cases performed.

A recent review of 40 cases aged under 55 showed evidence of causative trochlear dysplasia in more than 50%.

This was based on:

Trochlear dysplasia recorded on operative note 8

A positive crossing sign on a true lateral xray 19

A sulcus angle > 144° 20

Conclusion: Trochlear dysplasia frequently leads to severe symptomatic patello-femoral arthritis, often at an early age, and can be helped by isolated patello-femoral replacement. Since only 38 of the 385 cases had undergone re-alignment procedures it seems likely that the condition initially presents in a variety of ways.

Introduction: Trochlear dysplasia is an important anatomical factor in symptomatic patellar instability. The impression at surgery is that the dysplasia is predominantly an abnormality of the proximal trochlea. There is a mismatch between the bony and cartilaginous trochlear anatomy in normal knees. This study assessed the mismatch in dysplastic trochleas.

Methods: The MRI scans of 25 knees in 23 patients with patellar instability and trochlear dysplasia were reviewed retrospectively. Axial fat saturation images where used to assess cartilaginous and bony trochlear morphology. The following parameters were measured in the three most proximal images of each trochlea:

Cartilaginous and bony sulcus angles.

Inter and intra observer error was recorded.

Results: There were 15 females and 8 males with an average age of 20.4 years (14 30).

The average bony sulcus angle (SA) was 166.9 degrees (141 – 203) whereas the average cartilaginous SA was 184.8 degrees (152 – 222). In 74 of 75 axial images (98.6%) the cartilaginous SA was greater than the bony SA by an average of 17.6 degrees (3 45).

Conclusion: This study demonstrates that the cartilaginous trochlear morphology differs markedly from that of the underlying bony trochlea in patients with trochlear dysplasia. Although the bony trochlea was dysplastic, the cartilage morphology worsened this abnormal shape. Since cartilage is poorly represented on routine radiography and computed tomography, MRI is necessary to demonstrate both the bony and cartilaginous morphology to facilitate surgical planning.