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Introduction: The rationale for the use of mini-implants for partial resurfacing in the treatment of femoral chondral and osteochondral lesions is still under debate. The evidence supporting best practise guidelines is based on studies with low-level evidence. A consensus group of experts was convened to collaboratively advance towards consensus opinions regarding the best available evidence. The purpose of this article is to report the resulting consensus statements.

Methods: Twenty-five experts participated in a process based on the Delphi method of achieving consensus. Questions and statements were drafted via an online survey of two rounds, for initial agreement and comments on the proposed statements. An in-person meeting between the panellists was organised during the 2022 ESSKA congress to further discuss and debate each of the statements. A final agreement was made via a final online survey a few days later. The strength of consensus was characterised as: consensus, 51–74% agreement; strong consensus, 75–99% agreement; unanimous, 100% agreement.

Results: Statements were developed in the fields of patient assessment and indications, surgical considerations and postoperative care. Between the 25 statements that were discussed by this working group, 18 achieved unanimous, whilst 7 strong consensus.

Conclusion: The consensus statements, derived from experts in the field, represent guidelines to assist clinicians in decision-making for the appropriate use of mini-implants for partial resurfacing in the treatment of femoral chondral and osteochondral lesions. Level of evidence: Level V.

Background and purpose: Patients with focal cartilage lesions experience functional impairment. Results for biological treatments in the middle-aged patient is poor. Previous studies with focal prosthetic inlay resurfacing have shown a higher risk of conversion to total knee replacement at mid-term follow-up. A novel customized implant (Episealer, Episurf, Stockholm, Sweden) has been proposed to improve implant positioning and survival. The primary objective was to assess subjective-, objective function and implant survival at a minimum of five years after surgery.

Materials and methods: The inclusion criteria were patients aged 30–65 years with symptomatic focal chondral defects in the medial femoral condyle, International Cartilage Research Society grade 3 or 4 and failed conservative or surgical treatment. Minimum follow-up of 5 years. Clinical and radiologic assessments were made. Patient-reported outcome measurements at the latest follow-up were compared with the baseline data for the Knee injury and Osteoarthritis Outcome Score (KOOS), the EuroQoL (EQ-5D), the Tegner Activity Scale and a Visual Analog Scale of pain (VAS 0–10).

Results: Ten patients with the mean follow-up period of 75 months (60–86 months, SD 10) were included. Signs of osteoarthritis were seen in one patient (Ahlbäck 1). No cases with revision to knee replacement. VAS for pain and KOOS showed improvements that reached significance for VAS (p ≤ 0.001) and the KOOS subscores Pain (p = 0.01), ADL (p = 0.003), Sport and Recreation (p = 0.024) and Quality of Life (p = 0.003).

Conclusion: A good subjective outcome, a low risk of progression to degenerative changes and the need for subsequent surgery were seen at the mid-term follow-up with this customized focal knee-resurfacing implant.

Level of evidence: Prospective case series, level 4.

Background Full-depth cartilage lesions do not heal spontaneously and may progress to osteoarthritis (OA). Treatment for these lesions is warranted when symptomatic. At younger age, biological treatment remains the gold standard, but treatment in the middle-aged patient remains a clinical challenge and focal metal implants have been proposed. We aim to present the subjective outcome at 2 years and the risk of reoperation for any reason at midterm after surgery with a novel customized implant for focal femoral chondral lesions in the knee.

Methods In a prospective cohort study, 30 patients were included between January 2013 and December 2017 at 9 different clinics in Sweden. The primary outcome was subjective outcome measurements (Visual Analogue Scale [VAS], EuroQoL [EQ5D], Knee injury and Osteoarthritis Outcome Score [KOOS]) at a minimum of 2 years. The secondary outcome was reoperations for any reason during the follow-up period until December 2019 (mean of 55 months) studied retrospectively by analyzing medical records.

Results The VAS, EQ5D, and all the KOOS subscales showed significant improvements from preoperatively to the 2-year follow-up. The VAS showed the greatest improvement at the early (3 months) postoperative stage (P < 0.001). Five (7%) patients underwent reoperations and one of these was revised to hemiarthroplasty due to OA progression. No implant loosening was detected in any of the cases.

ConclusionsThis customized resurfacing metal implant showed good safety and patient satisfaction. The risk of OA progression and implant loosening is low. Subjective function and pain improved significantly.

Iron is an essential micronutrient for oxygen transport and mitochondrial metabolism and is critical for physical performance. Compromised iron stores are more commonly found among athletes, and females are especially at risk. Iron deficiency is generally treated using oral iron supplements. However, only a small proportion of ingested iron is absorbed, necessitating higher intakes, which may result in adverse side effects, reduced compliance, and inefficient repletion of iron stores. The probiotic strainLactobacillus plantarum299v (Lp299v) significantly increases intestinal iron absorption in meal studies. The present study was conducted to explore the effects of 20 mg of iron with or without Lp299v on iron status, mood state, and physical performance. Fifty-three healthy non-anemic female athletes with low iron stores (ferritin < 30 mu g/L) were randomized, and 39 completed the study. Intake of Lp299v with iron for four weeks increased ferritin levels more than iron alone (13.6 vs. 8.2 mu g/L), but the difference between the groups was not significant (p= 0.056). The mean reticulocyte hemoglobin content increased after intake of Lp299v compared to control (1.5 vs. 0.82 pg) after 12 weeks, but the difference between the group was not significant (p= 0.083). The Profile of Mood States (POMS) questionnaire showed increased vigor with Lp299v vs. iron alone after 12 weeks (3.5 vs. 0.1,p= 0.015). No conclusive effects on physical performance were observed. In conclusion, Lp299v, together with 20 mg of iron, could result in a more substantial and rapid improvement in iron status and improved vigor compared to 20 mg of iron alone. A larger clinical trial is needed to further explore these findings as well as the impact of Lp299v on physical performance.

Purpose: Managing focal cartilage injuries in the middle-aged patient poses a challenge. Focal prosthetic inlay resurfacing has been proposed to be a bridge between biologics and conventional joint arthroplasty. Patient selection and accurate implant positioning is crucial to avoid increased contact pressure to the opposite cartilage surface. A customized femoral condyle implant for focal cartilage injuries was designed to precisely fit each patient’s individual size and location of damage. The primary objective was to assess implant safety profile, surgical usability of the implant and instruments, and implant migration with radiostereometric analysis (RSA). Methods: Ten patients 36–56 years with focal chondral defects, ICRS 3–4 of the femoral cartilage and failed earlier conservative or surgical interventions with VAS pain > 40. The patients were followed for 2 years with subjective outcome measures (VAS, EQ5D, KOOS) and RSA. The customized implant and guide instruments were manufactured by computer-aided design/computer-aided manufacturing (CAD/CAM) techniques using MRI data. Results: VAS, EQ5D and KOOS showed improvements that reached significance for VAS (p ≤ 0.001), Tegner (p = 0.034) and the KOOS subscores ADL (p = 0.0048), sport and recreation (p = 0.034) and quality of life (p = 0.037). VAS and KOOS scores improved gradually at 3, 6 and 12 months. The improvements in EQ5D, KOOS pain and KOOS symptoms did not reach statistical significance. No infections, deep venous thrombosis or other complications occured in the postoperative period. No radiographic signs of damage to the opposing tibial cartilage was noted. The surgical usability of implants and instruments were good. RSA did not show any implant migration. Conclusion: This is the first clinical report of a new customized, focal knee resurfacing system. The short-term implant safety and patient-related outcome measures showed good-to-excellent results. Level of evidence: Prospective case series, Level 4.

Objective The skeleton has been suggested to be involved in energy metabolism through osteocalcin (OC), an osteoblast-specific molecule. The objective of this study was to investigate whether high impact exercise stimulating bone formation would lead to changes in glucose and lipid metabolism independent of cardiorespiratory effects, and if OC mediates this association.

Design Prospective intervention study.

Methods Fifty men aged 20-32 years were allocated to an intervention group or a control group. The intervention group completed six different types of jumps in sets of five, with the frequency of these exercises gradually increasing over 8 weeks. At baseline and after 8 weeks, glycerol concentrations were measured in fat tissue as a marker of lipolysis by using microdialysis. Blood samples were assayed for OC and markers of glucose and lipid metabolism. Physical activity was measured using an accelerometer.

Results After adjustment for confounders at baseline and changes in physical activity during the intervention period, the intervention was associated with a decrease in levels of glucose (p = 0.04), adrenalin (p = 0.03) and OC (p=0.04) after adjusting for baseline levels and changes in physical activity. No other differences between the groups were significant, although the trends of the metabolic variables favored the intervention group.

Conclusions The results of this study suggest that high impact loading on the skeleton may affect glucose metabolism independent of the level of aerobic exercise.

Background: Physical activity has been recommended for the prevention and even treatment of osteoporosis because it potentially can increase bone mass and strength during childhood and adolescence and reduce the risk of falling in older populations. However, few reports have systematically investigated the effect of physical activity on bone in men and women of different ages.

Purpose: The goal of this study was to review the literature relating to the effect of physical activity on bone mineral density in men and women of various ages.

Method: This review systematically evaluates the evidence for the effect of physical activity on bone mineral density. Cochrane and Medline databases were searched for relevant articles, and the selected articles were evaluated.

Results: The review found evidence to support the effectiveness of weight bearing physical activity on bone accrual during childhood and adolescence. The effect of weight bearing physical activity was site-specific. In contrast, the role of physical activity in adulthood is primarily geared toward maintaining bone mineral density. The evidence for a protective effect of physical activity on bone is not as solid as that for younger individuals.

Conclusions: The effect of weight bearing physical activity is seen in sites that are exposed to loading. There also seems to be a continuous adaptive response in bone to loading. Additional randomized, controlled studies are needed to evaluate the effect of physical activity in the elderly.

CONTEXT: The association between retinol and bone mineral density (BMD) in males after puberty has not been fully investigated previously. OBJECTIVE: To investigate the association between retinol, retinol-binding protein-4 (RBP-4), BMD (g/cm(2)), abdominal fat mass, and markers of bone metabolism in young men. DESIGN: Longitudinal study. PARTICIPANTS: Seventy-eight healthy males with a mean age of 22.6+/-0.7 years at baseline. A follow-up was conducted in 73 of the participants 2.0+/-0.4 years later. MAIN OUTCOME MEASURES: Associations between serum concentrations of retinol and RBP-4, and BMD of the total body, lumbar spine, and hip, serum concentrations of osteocalcin, and carboxy terminal telopeptide of type 1 collagen (CTX), were investigated. RESULTS: Both retinol and RBP-4 showed an inverse relationship with that of osteocalcin (r=-0.23 to -0.25, P<0.05). Levels of RBP-4 (r=0.26, P=0.02) and osteocalcin (r=-0.23, P=0.04) were also related to abdominal fat mass, and the relationship between RBP-4, retinol, and osteocalcin disappeared after adjusting for this influence of abdominal fat mass. Neither retinol nor RBP-4 concentrations were associated with BMD at any site, CTX as baseline, or changes in BMD during the 2-year follow-up period. Levels of RBP-4 showed a strong association with levels of retinol (r=0.61, P<0.001). CONCLUSION: We found a negative association between the bone formation marker osteocalcin with retinol and RBP-4. The association disappeared when adjusting for the influence of abdominal fat mass. Neither retinol nor RBP-4 were associated with peak BMD in young men.