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Study Type: Prospective cohort study (Level 2 evidence)

Key Question: Are within-pitcher changes in game pitch count and fastball velocity associated with shoulder and elbow injury risk in collegiate baseball pitchers?

Key Findings:

• 187 pitchers followed across 9,890 exposure days; 22 (12%; 95% CI 7.5–17.2%) sustained an arm injury.
• Injury hazard showed a nonlinear (parabolic) association with deviation of pitch count from the individual pitcher's seasonal mean.
• Injury hazard also showed a nonlinear (parabolic) association with a fall in fastball velocity relative to the pitcher's own mean. Hazard ratios were not reported in the abstract.

Clinical Relevance: Individualised workload and velocity monitoring may help identify overhead athletes at risk, though the data come from US collegiate baseball and are of limited direct relevance to UK practice.

Limitations: Few injury events (n=22) in a single summer season limits precision and the ability to adjust for confounders; effect sizes are not given in the abstract.

Study Type: Controlled laboratory study (preclinical, in vivo rat model). Sample size not stated in the abstract.

Key Question: What is the maximum osteochondral defect diameter that can heal from a single microfracture perforation, and how does repair spread spatially from that channel?

Key Findings:

• At 8 weeks, 1 mm and 1.5 mm defects showed better filling, subchondral bone reconstruction and COL II expression than 2 mm defects (all P < .05), with no significant difference between 1 mm and 1.5 mm.
• Reparative tissue (safranin O staining, COL II) concentrated around the perforation tract and declined significantly towards the defect periphery (P < .05).
• The authors propose ~1.5 mm as the critical defect gap for single-hole microfracture.

Clinical Relevance: The findings suggest each microfracture channel has limited effective coverage, which may inform perforation spacing and density, but the findings cannot be translated directly to human defect sizes or current NHS practice.

Limitations: Small-animal model with 1 mm deep defects and 8-week follow-up; the 1.5 mm threshold cannot be extrapolated to human cartilage thickness, loading or long-term outcomes.

Study Type: Controlled laboratory (biomechanical) study using 10 fresh-frozen cadaveric knees on a 6-DOF robotic system.

Key Question: Does the femoral fixation point (ALL insertion vs distal Kaplan fibres) or fixation flexion angle (30° vs 60°) of LET alter ACL graft force and tibiofemoral kinematics after ACLR?

Key Findings:

• No differences between any of the four LET configurations for ACL graft force, internal rotation or anterior tibial translation.
• Adding LET reduced ACL graft force in internal rotation in all configurations (about 15–20 N at 0°, about 20 N or 51–55% at 30°, about 4–5 N at 60°; all P < .05).
• LET also reduced internal rotation by about 2–6° (15–23%) across flexion angles, with values falling beyond the native knee, indicating overconstraint.

Clinical Relevance: Surgeons may have latitude in LET femoral tunnel position and fixation angle without altering biomechanical effect, though the overconstraint seen is relevant to UK practice as LET use with ACLR expands following the STABILITY trial.

Limitations: Small cadaveric sample (n = 10) with time-zero testing only, so there is no assessment of healing, long-term graft behaviour or clinical outcomes, and possible type II error given the null comparisons.

Study Type: Retrospective case series (Level 4), single-centre data, 2006–2020.

Key Question: What are the mid-term outcomes, return-to-sport rates and predictors of failure after primary arthroscopic Bankart repair (without remplissage) in patients ≤24 years with <10% glenoid bone loss?

Key Findings:

• Of 96 patients followed up (mean 68 months), recurrence occurred in 33.3% and revision surgery in 19.8%; contact sport participation was associated with failure.
• 96.1% returned to sport, but only 57.1% regained preinjury level; fewer preoperative dislocations predicted full return (P = .04).
• PROMs and satisfaction were high (median 9/10), though this includes patients with recurrence.

Clinical Relevance: A one-in-three recurrence rate in young contact athletes supports cautious consent and consideration of augmentation (e.g., remplissage) or alternative stabilisation, particularly given NHS revision burden.

Limitations: Retrospective design with 14% loss to follow-up and no comparator arm limits causal inference and may underestimate failure.

Study Type: Prospective cohort study (Level 2), with matched uninjured controls.

Key Question: How do serum markers of inflammation and cartilage metabolism evolve over the first year after ACL reconstruction compared with uninjured controls?

Key Findings:

• MCP-1 (inflammation) and COMP (cartilage turnover) were higher than controls at all time points (pre-op, 6 and 12 months) and did not fall postoperatively.
• C2C:CPII (collagen degradation-to-synthesis ratio) rose at 12 months versus pre-op and 6 months, and exceeded controls (Padj = .001). MMP-3 rose by 6 months but did not differ from controls.
• Pre-op MCP-1, MMP-3 and COMP predicted their post-op levels (all P ≤ .006).

Clinical Relevance: Reconstruction and standard rehabilitation appear not to normalise the joint's biological response, which may help explain post-traumatic osteoarthritis risk and supports investigating adjuncts in the NHS ACL pathway.

Limitations: Small sample (n=33 per group) with serum-only biomarkers and no clinical, imaging or long-term osteoarthritis outcomes, so prognostic value is unproven.

Study Type: Retrospective case series (Level 4), n=40, 3D CT-based measurements.

Key Question: Do global track parameters correlate with established metrics of bipolar bone loss and engagement risk in anterior shoulder instability?

Key Findings:

• Mean global track angle was 73.5° ± 13.7° against a mean critical value of 65.5° ± 6.1°. A cutoff of <66° was associated with off-track lesions, but discrimination was poor (AUC 0.649; 95% CI 0.458–0.840).
• Glenoid angle showed a moderate inverse correlation with glenoid bone loss (R² = 0.43); each 10% increase in loss corresponded to a 4.5° decrease. A critical glenoid angle of ~23° corresponded to 13.5% loss (AUC 0.757; 95% CI 0.591–0.922).

Clinical Relevance: Global track is a conceptually appealing continuous measure that may refine bipolar bone loss assessment beyond the glenoid track/occupancy ratio, but it is not yet ready to guide decisions on Latarjet or remplissage in routine NHS practice.

Limitations: Small, retrospective sample with no clinical outcome data (recurrence, engagement confirmed arthroscopically), and wide confidence intervals indicating poor predictive performance.

Study Type: Prospective, multicentre, double-blind RCT (3 Chinese hospitals, n=240).

Key Question: Does a standardised, multicomponent PRP pathway improve outcomes over physician-directed conventional PRP care in KL grade I–II knee OA?

Key Findings:

• At 12 months, the pathway group showed greater improvement in VAS (MD −2.98, 95% CI −3.64 to −2.32), WOMAC total (MD −8.63, −11.35 to −5.90) and IKDC (MD 10.25, 8.37 to 12.13); all P<.001.
• Adverse events: 14.8% (17/115) versus 31.9% (36/113) (P=.003). Satisfaction favoured the pathway (OR 1.79, 1.11–2.89).
• Costs were similar (CN¥15,200 vs 14,754); ICER CN¥66 per WOMAC point.

Clinical Relevance: This supports standardising PRP delivery (selection, leukocyte-poor preparation, ultrasound guidance, staged rehabilitation) rather than ad hoc use, though PRP remains non-routine for knee OA in NHS practice.

Limitations: Bundled components and no placebo arm mean the trial cannot establish PRP efficacy or identify which element drives benefit; attrition (about 5%) and single-country setting limit generalisability.

Study Type: Descriptive laboratory study (cadaveric anatomical study, n=10 fresh-frozen knees, mean age 70.7 years).

Key Question: What are the attachment geometry, anterior extent, and radiographic landmarks of the deep medial collateral ligament (dMCL)?

Key Findings:

• The dMCL had a broad anteromedial capsular extension (anterior margin 27.0 ± 3.4 mm from the posterior sMCL), blending posteriorly with the posterior oblique ligament.
• Femoral attachment: 10.7 ± 1.5 mm wide, centred 5.1 mm posterior and 12.4 mm distal to the medial epicondyle, and 10.6 mm distal to the sMCL femoral attachment.
• Tibial attachment: 29.3 ± 3.7 mm wide, 2.2 mm distal to the joint line. Radiographically, the femoral centre lay 7.9 mm from the sMCL femoral centre, and the tibial centre 15.0 mm proximal to the proximal sMCL tibial attachment.

Clinical Relevance: These measurements offer surgeons intraoperative and radiographic reference points for identifying the dMCL and potentially refining medial-sided knee reconstruction.

Limitations: Small, elderly cadaveric sample limits generalisability to younger, active patients, and no biomechanical or clinical outcome data were reported.