Unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO) are well-established operative interventions in the treatment of knee osteoarthritis (KOA). However, which of these interventions is more beneficial, to patients with KOA, is not known and remains a topic of much debate.

Aims: (i) To determine whether UKA or HTO is more beneficial in the treatment of isolated medial compartment KOA, via an assessment of patient-reported outcome measures (PROMs). (ii) To investigate the relationship between PROMs and radiographic parameters of knee joint orientation/alignment.

This longitudinal observational study assessed a total of 42 patients that had undergone UKA (n=23) or HTO (n=19) to treat isolated medial compartment KOA. The PROMs assessed, pre-operatively and 1-year post-operatively, consisted of the: self-administered comorbidity questionnaire; short form-12; oxford knee score; knee injury and osteoarthritis outcome score; and the EQ-5D-5L. The radiographic parameters of knee joint alignment/orientation assessed, pre-operatively and 8-weeks post-operatively, included the: hip-knee-ankle angle; mechanical axis deviation; and the angle of the Mikulicz line.

Statistical analysis demonstrated an overall significant (p<0.001), pre-operative to post-operative, improvement in the PROM scores of both groups. There were no significant differences in the post-operative PROM scores of the UKA and HTO group. Correlation analyses revealed that pre-operatively, a more distolaterally angled Mikulicz line was associated with worse knee function (p<0.05) and overall health (p<0.05); a relationship that, until now, has not been investigated nor commented upon within the literature.

UKAs and HTOs are both efficacious operations that provide a comparable degree of clinical benefit to patients with isolated medial compartment KOA. To further the scientific/medical community's understanding of the factors that impact upon health-outcomes in KOA, future research should seek to investigate the mechanism underlying the relationship, between Mikulicz line and PROMs, observed within the current study.

Meniscal tears are the most common injury in the knee, affecting 66/100,000 people/year. Surgical treatment includes arthroscopic meniscectomy or meniscal repair. Little is known regarding medium-term outcomes following these procedures in isolated meniscal tears. This study aims to quantitatively evaluate patients with meniscal tears, and those who have undergone meniscectomy and meniscal repair using validated patient reported outcome measures (PROMs), further exploring factors which affect surgical outcomes.

This observational study screened 334 patients who underwent arthroscopic surgery at South Tyneside Hospital since August 2013. 134 patients with isolated meniscal tears were invited to complete postal PROMs. A combination of patient notes and radiological imaging was used to collect information of interest including age, gender, knee-laterality, injured meniscus, tear pattern, procedure performed, complications, and associated injuries.

A total of 115 patients (pre-operative patients with current meniscal tear (n=36), meniscectomy (n=63), meniscal repair (n=16)) were included in the analysis with 96% successful PROM completion. Both meniscectomy and meniscal repairs (mean 55-months follow-up) showed better outcomes than pre-operative patients with meniscal tears. Meniscal repairs demonstrated superior outcomes across all PROMs when compared to meniscectomy, with a greater mean overall KOOS score of 17.2 (p=0.009). Factors including higher pre-operative Kellgren-Lawrence Grade, pre-operative articular cartilage lesions and bilateral meniscectomies were shown to negatively influence outcomes.

Both meniscectomy and meniscal repair maintain clinical benefit at mean 55-months follow-up, affirming their use for treatment of meniscal tears. When feasible, meniscal repair should be performed preferentially over meniscectomy in isolated meniscal tears. Identified predictive factors allow adequate treatment stratification in specific patient groups.