Growth Plate Injuries

A growth plate, or physis, is a zone of cartilage near the ends of long bones where lengthwise growth happens through childhood and adolescence. Because cartilage is mechanically weaker than the surrounding bone, the physis can be injured by forces that an adult bone would absorb without issue. That is why Salter-Harris fractures and apophysitis (irritation where a tendon pulls on a growth area) are problems of childhood and the teen years rather than adulthood.

It is usually benign and self-limiting, but it is real pain and it can sideline a young athlete from sport they care about. The tibial tubercle stays tender and prominent because the patellar tendon pulls repeatedly on a growth area that has not yet fused into solid bone (an immature apophysis). Management is mostly load modification, relative rest from the activities that aggravate it most, calf and quadriceps mobility, and reassurance. Symptoms usually settle once that growth area fuses, in the mid to late teens.

Rarely. For most apophysitis patterns, such as Sever's, Osgood-Schlatter, and Sinding-Larsen-Johansson, complete rest is not the goal. DiFiori and colleagues' 2014 position statement on youth overuse injuries supports modifying training load, reducing volume of the most aggravating tasks, and keeping the child engaged in sport where possible. Complete rest is reserved for acute fractures or when pain is changing how the child walks and moves.

Salter-Harris injuries are acute fractures through or near the growth plate, usually after a specific traumatic event. They are classified Type I through V based on where the fracture line runs, and types III, IV, and V have higher risk of growth disturbance. Apophysitis is a gradual overuse injury where a tendon pulls on a growth area at a bony bump, such as below the kneecap (the tibial tubercle) or at the back of the heel (the calcaneus), without a fracture. Management and urgency differ substantially.

The honest answer is that most growth plate injuries in children heal without any long-term effect on growth, but a minority do slow or stop growth there, partly or fully (growth arrest), especially with Salter-Harris types III, IV, and V. That is why sudden injuries that may involve the growth plate are followed up by the orthopaedic team over months, not just weeks. Apophysitis conditions do not typically cause long-term deformity.

Broad principles from the 2014 position statement by DiFiori and colleagues include at least one to two rest days per week, avoiding year-round single-sport specialisation before mid-adolescence, keeping training hours per week from exceeding the child's age as a rough guide, and respecting pain signals rather than pushing through. Coaches, parents, and the child all have a role in the conversation, not just the physio.

If the injury is acute with suspected fracture, yes, imaging is part of the initial workup. For apophysitis with a typical picture, such as a 12-year-old gymnast with pain in both heels and pain when the heels are squeezed from both sides, imaging often adds little. When the story does not match the exam, when symptoms are not settling as expected, or when a higher-risk pattern is suspected, imaging can change the plan, and then I flag it to your family doctor or specialist and refer you.

For apophysitis conditions, return to sport is graded rather than binary. Once pain is tolerable with daily activity and single-leg loading, a progressive return to running, then jumping, then sport-specific drills, then full training, is the usual path. For Salter-Harris fractures, return is guided by the orthopaedic team and depends on the fracture type, healing, and any activity restrictions they set.