Tibial Spine (Eminence) Fracture: reduction and fixation with bioabsorbable pins
Five-phase protocol after reduction and fixation of a tibial eminence fracture with bioabsorbable pins (Smart Nails), screws or suture: the paediatric equivalent of an ACL injury, except that here bone heals, not ligament.
Brace 4 weeks · Full weight bearing 6 weeks · Running 4 months · Pivoting sport 6-9 months
These documents are protocol templates for information and education only: they do not replace the rehabilitation prescription for the individual case. Timing, loading and progressions must always be adapted to the patient, the lesion pattern, the surgical technique used and the clinical course, in collaboration between orthopaedic surgeon, physiotherapist and, where appropriate, physiatrist. Progression is driven by objective criteria, not by the calendar alone.
In children and adolescents with open physes, the bone of the intercondylar eminence is weaker than the anterior cruciate ligament attached to it. A twisting injury that would tear the ligament in an adult therefore avulses a bony fragment from the tibial plateau instead: this is a tibial spine (eminence) fracture. The ligament is intact, but its anchorage has lifted off.
The biological advantage is real: bone heals in 6-8 weeks, far faster than a reconstructed graft, which takes months to integrate. The main risk is therefore not failure of healing but stiffness: arthrofibrosis (loss of extension or flexion from scar tissue) is the most frequent complication after this operation, reported in a significant proportion of cases immobilised for long periods. The practical message is the opposite of ACL reconstruction: here time works against motion, and motion must be restored early.
The Meyers and McKeever classification describes fragment displacement: type I (undisplaced, usually treated in a cast), type II (hinged posteriorly), type III (completely displaced) and type IV (comminuted or rotated). Irreducible type II, type III and type IV injuries are generally treated arthroscopically.
Fixation may use bioabsorbable pins such as Smart Nails (polylactic acid polymer), metal screws, or high-strength suture anchored to the tibia. Bioabsorbable pins have two relevant advantages in growing patients: no second operation for removal, and placement that can avoid problematic transit through the growth plate, which in the proximal tibia contributes substantially to limb growth. Their stability is, however, lower than a metal screw in hard bone, so rehabilitation progression remains surgeon-guided and never forced.
One point to explain to families: even after perfect bony healing, mild anterior laxity may remain — measurable but often asymptomatic — because the ligament had already stretched at the time of injury. What matters clinically is functional stability, i.e. the absence of giving-way episodes during sport.
Key parameters
- Brace
- Hinged brace locked in extension for walking in the first 2-4 weeks, progressively unlocked for exercise; in young children a cast or fixed brace for 3-4 weeks is sometimes used.
- Weight bearing
- Touch-down or partial weight bearing with crutches for 2-4 weeks with the brace locked in extension, then progression to full weight bearing by week 6.
- ROM
- Immediate full extension; guided flexion: 0-30/45° in week 1, 0-60° at 2 weeks, 0-90° at 4 weeks, full ROM at 6-8 weeks. Progression may be slightly more cautious with bioabsorbable pins.
- Main risk
- Arthrofibrosis (loss of extension or flexion). A stiff knee at 6 weeks requires immediate clinical review, not watchful waiting.
- Bone healing
- Radiographic check at 4-6 weeks; typical union at 6-8 weeks.
- Running
- Usually from months 3-4, with full ROM, a dry knee and quadriceps ≥80%.
- Return to sport
- Non-contact sport at 4-6 months; pivoting and contact sport at 6-9 months with functional tests passed and clinical stability.
What the surgery does
Bioabsorbable pins, screws or suture: what changes
The choice of fixation depends on fragment size and quality, patient age and proximity of the growth plate. It mainly changes how cautiously flexion is progressed in the first weeks.
| Bioabsorbable pins (Smart Nails) | Metal screws or high-strength suture | |
|---|---|---|
| Material | Bioabsorbable polymer (polylactic acid) that degrades progressively over months. | Titanium or steel screws, or high-strength fibre suture anchored to the tibia. |
| Second operation | Not required: the pin resorbs. | Screws may need removal, especially if prominent or symptomatic. |
| Relationship with the physis | Can be placed sparing the growth plate; ideal in children with very active physes. | Suture is physeal-sparing; screws require careful placement to avoid crossing the physis. |
| Mechanical strength | Good but lower than a metal screw: flexion progression is more cautious in the first weeks. | High with screws; suture provides excellent hold even in comminuted fragments. |
| Comminuted fragment | Less suitable when the fragment is in several small pieces. | Suture is often the best option because it gathers the fragments. |
| Rehabilitation | Same goals, with slightly more gradual flexion release in the first 3-4 weeks. | Usually allows slightly faster flexion progression, always on the surgeon’s instruction. |
In every case the priority is the same: regain full extension early and reach 90° of flexion within 4-6 weeks to prevent arthrofibrosis.
Loading timeline
Range of motion progression
Milestones at a glance
- Days 0-10Full extension achieved
- 2 weeks60° flexion, brace unlocked for exercise
- 4 weeks90° flexion, radiographic check
- 6 weeksFull weight bearing, brace discontinued
- Months 2-4Strength ≥80%, stable full ROM
- Months 4-6Running, plyometrics, agility
- Months 6-9Return to pivoting sport
Phases of the pathway
Phase 1 — Protecting the fixation with immediate extension
Weeks 0-2
Goals
- •Protect the fixation
- •Obtain full extension immediately
- •Prevent quadriceps inhibition and arthrofibrosis
What to do
- •Hinged brace locked at 0° for walking and at night; unlocked for exercise within the authorised arc (usually 0-30/45°)
- •Daily passive extension: prone hangs, 10 minutes 3-4 times daily
- •Quad sets, braced straight-leg raise, patellar mobilisation
- •Cryotherapy and compression 4-6 times daily, limb elevated
- •Walking with crutches and prescribed load, brace locked in extension
Restrictions and precautions
- •No flexion beyond the authorised arc
- •No resisted hamstring work (deep loaded flexion stresses the fixation area)
- •No twisting or loading on a flexed knee
Criteria to progress
- ☐Full active and passive extension (0°)
- ☐Straight-leg raise without extensor lag
- ☐At least 45-60° flexion per protocol
- ☐Decreasing pain and effusion
Note for the physiotherapist
In this condition, excessive caution is the most costly error. Extension must be obtained in the first 7-10 days: regaining it after week 6 often requires manipulation under anaesthesia or arthrolysis.
Phase 2 — Restoring flexion and weight bearing
Weeks 2-6
Goals
- •90° flexion at 4 weeks and full ROM at 6-8 weeks
- •Full weight bearing without limp
- •Quadriceps reactivation
What to do
- •Guided flexion progression: heel slides, gravity-assisted seated flexion, stationary bike with no resistance once past 100-105°
- •Progressive brace unlocking and weaning, usually between weeks 4 and 6
- •Load progression to full weight bearing; mirror gait re-education
- •Closed-chain strengthening: mini-squats 0-45°, glute bridge, low-load leg press
- •Radiographic check at 4-6 weeks to confirm union
Restrictions and precautions
- •No impact, no running
- •Avoid aggressive forced passive flexion with bioabsorbable pin fixation before healing is confirmed
Criteria to progress
- ☐ROM 0-120° or more
- ☐Walking without crutches, brace or limp
- ☐Absent or minimal effusion
- ☐Radiographs showing signs of union
Note for the physiotherapist
If at 6 weeks flexion is below 90° or extension is incomplete, inform the surgeon immediately: this is the window in which targeted mobilisation prevents further surgery.
Phase 3 — Strength and knee control
Months 2-4
Goals
- •Stable, full symmetrical ROM
- •Quadriceps ≥80% of the other side
- •Single-leg alignment control
What to do
- •Progressive strengthening: squats, lunges, step-ups and step-downs, single-leg press, single-leg bridge
- •Posterior chain and hamstrings (introduced gradually, without early maximal loads)
- •Single-leg proprioception, unstable surfaces, dual task
- •Bike, swimming, elliptical for conditioning; introduction of deep-water running
- •Clinical stability assessment (Lachman, pivot shift) and instrumented testing if doubtful
Restrictions and precautions
- •No cutting or full-intensity sport-specific drills
Criteria to progress
- ☐Full symmetrical ROM
- ☐Quadriceps ≥80%
- ☐20 cm step-down without dynamic valgus or pain
- ☐No effusion after activity
Phase 4 — Running, impact and agility
Months 4-6
Goals
- •Running and plyometrics without symptoms
- •Strength ≥90%
- •Preparation for sporting skills
What to do
- •Interval return-to-running programme, 10% weekly volume progression
- •Progressive plyometrics: double-leg → single-leg → jumps with controlled landing
- •Linear agility, then wide and sharp cutting; deceleration work
- •ACL-injury prevention neuromuscular training (dynamic valgus control, landing mechanics)
Criteria to progress
- ☐20-30 minutes of continuous running without pain or swelling
- ☐Hop tests with LSI ≥85-90%
- ☐Quadriceps and hamstrings ≥90%
- ☐No giving-way episodes
Phase 5 — Return to sport and growth surveillance
Months 6-9 and follow-up
Goals
- •Graded return to competition
- •Confirm absence of growth disturbance
- •Prevent subsequent injury
What to do
- •Graded reintegration: partial training → full training → competition
- •Ongoing preventive neuromuscular programme (FIFA 11+ or equivalent)
- •Clinical and radiographic follow-up at 6-12 months in patients with open physes, to exclude angular deformity or leg-length discrepancy
- •Education: mild residual laxity is common and does not contraindicate sport when functional stability is good
Criteria to progress
- ☐Test battery with LSI ≥90%
- ☐Satisfactory clinical stability and no giving-way episodes
- ☐Full ROM maintained over time
- ☐Surgeon clearance and adequate subjective confidence (ACL-RSI or analogue scale)
Return to sport / full activity
Non-contact sport usually at 4-6 months; pivoting and contact sport at 6-9 months. Timelines are shorter than after ACL reconstruction because bone heals rather than a graft, but functional criteria remain the same.
- ☐Quadriceps and hamstring strength with LSI ≥90%
- ☐Hop test battery (single, triple, crossover, 6 m timed) with LSI ≥90%
- ☐Full symmetrical ROM, no effusion
- ☐No giving-way episodes and clinically acceptable Lachman test
- ☐Drop-jump landing without dynamic valgus
- ☐Pedi-IKDC or Lysholm ≥90 and adequate subjective confidence
In patients with open physes, clinical and radiographic follow-up to 12 months is advisable to exclude growth disturbance. Mild residual anterior laxity is common: when not associated with functional instability, it does not delay return to sport.
Red flags: stop and contact us
- •Knee not regaining full extension within 2-3 weeks or 90° flexion within 6 weeks (suspected arthrofibrosis: contact immediately)
- •Sudden locking (possible fragment or implant displacement)
- •Large persistent effusion or rapid recurrence after loading
- •Acute pain after a new injury with a sense of giving way
- •Fever, redness, warmth or discharge from arthroscopic portals
- •In growing patients: development of angular deformity or leg-length difference in the following months
Guidelines and literature
- Meyers MH, McKeever FM. Fracture of the intercondylar eminence of the tibia. J Bone Joint Surg Am.
- Gans I, Baldwin KD, Ganley TJ. Treatment and Management Outcomes of Tibial Eminence Fractures in Pediatric Patients: A Systematic Review. Am J Sports Med 2014.
- Patel NM et al. Tibial Spine Research Interest Group — arthrofibrosis and outcomes after tibial spine fracture. J Pediatr Orthop.
- Bogunovic L, Tarabichi M, Nepple JJ. Tibial eminence fractures: current concepts. Curr Rev Musculoskelet Med.
- ESSKA Paediatric Sports Medicine — consensus on paediatric knee injuries.
Key exercises, step by step
Each exercise belongs to a specific phase: do not anticipate them. Dosage is indicative and must be adapted by your physiotherapist.
1. Quadriceps isometric contraction (quad set)
From day 1
- •Lie on your back with the leg straight and a rolled towel under the ankle.
- •Push the knee down by tightening the thigh, as if flattening the bed.
- •The heel lifts slightly: that means you are reaching full extension.
Dosage: 10 contractions of 5 seconds, 4-6 times a day
2. Prone hang (passive extension)
From day 1 — the most important exercise
- •Lie face down on a bed with the operated leg over the edge from the knee down.
- •Let the weight of the leg extend the knee: no pushing, just gravity.
- •If needed, add a small ankle weight (0.5-1 kg) after the first week.
Dosage: 10 minutes, 3-4 times a day
3. Straight-leg raise
From day 1-2
- •Lying on your back, first tighten the thigh until the knee locks straight.
- •Lift the straight leg about 30 cm, hold 3 seconds and lower slowly.
- •If the knee bends while lifting, the quadriceps is not ready yet: go back to quad sets.
Dosage: 3 sets of 10, twice a day
4. Heel slides (flexion recovery)
Within the authorised arc
- •Lying on your back, slowly slide the heel towards the buttock.
- •Stop at the angle allowed by the protocol, hold 5 seconds and return.
- •A towel under the heel makes sliding easier.
Dosage: 3 sets of 10, 3 times a day
5. Load progression using scales
Crutch-weaning phase
- •Place the operated foot on bathroom scales while standing between crutches.
- •Learn what 20 kg, 40 kg and half your body weight feel like: memorise the sensation.
- •Increase one level per week, only if pain and swelling do not appear.
Dosage: 5 minutes of load training per day
6. Mini-squat 0-45°
From the full weight-bearing phase
- •Standing, feet hip-width apart, weight evenly distributed.
- •Bend the knees to about 45°, keeping the knees aligned over the feet.
- •Rise by pushing through the heels, without letting the knee collapse inwards.
Dosage: 3 sets of 12, 3-4 times a week
7. Glute bridge
From week 2
- •Lie on your back, knees bent, feet flat on the floor.
- •Lift the pelvis by squeezing the glutes until shoulders, hip and knee are aligned.
- •Lower slowly without arching the back.
Dosage: 3 sets of 12-15, on alternate days
8. Controlled step-down
Strength phase (from month 3)
- •Stand on a 15-20 cm step on the operated leg.
- •Lower slowly with the other foot, touching the floor with the heel, over 3 seconds.
- •The standing knee must stay aligned over the foot: if it collapses inwards, lower the step.
Dosage: 3 sets of 8-10 per side, 3 times a week
9. Single-leg balance
From the full weight-bearing phase
- •Stand on one leg, knee slightly bent, looking ahead.
- •Progress: eyes open → eyes closed → soft surface → catching a ball.
- •The pelvis must stay level: if it drops on one side, the gluteus medius is weak.
Dosage: 3 x 30 seconds per side, daily
10. Progressive plyometrics
Impact phase
- •Start with two-foot hops on the spot, landing softly with bent knees.
- •Progress to front-back and lateral hops, then single-leg.
- •Landings must be silent: noise means insufficient shock absorption.
Dosage: 2-3 sets of 10-20 contacts, 2-3 times a week
11. Agility and change of direction
Pre-return-to-sport phase
- •Shuttle runs, figure-of-8, cone slaloms: wide turns first, then sharper cuts.
- •Add unanticipated (cued) direction changes only at the end.
- •No drill should be performed with pain or a feeling of an unsafe knee.
Dosage: 2 sessions a week, within training
Frequent questions
Why insist on early motion here, when ACL reconstruction is more cautious?
Because the biological problem is different. After ACL reconstruction we wait for a graft to integrate; here the ligament is intact and only a bony fragment must heal, which happens in 6-8 weeks. Stiffness becomes the real enemy: arthrofibrosis is the most frequent complication after this operation.
Do bioabsorbable pins really dissolve?
Yes: they are made of polylactic acid polymer and are degraded and resorbed over months, leaving healed bone behind. The advantage is avoiding a second operation for removal, particularly useful in growing patients.
Will the knee be as stable as before?
In most cases functional stability is good. Mild anterior laxity may persist — measurable on testing but often asymptomatic — because the ligament had already stretched during the injury. What matters is the absence of giving-way episodes in sport.
Can the fracture disturb tibial growth?
It is rare, but the proximal tibial physis contributes substantially to limb length: clinical and radiographic follow-up is therefore planned in the following months to check alignment and length symmetry.
Is swelling in the evening normal?
Mild evening swelling in the first weeks is common. It becomes a warning sign when it increases day by day, appears after every session, or does not settle within 24-48 hours with ice and elevation: in that case the weekly load is excessive and should be reduced by one level.
Can I do physiotherapy only once a week?
The physiotherapy session is for setting up, correcting and progressing the programme. The result, however, depends on the exercises performed at home every day: a short daily home programme is worth more than an isolated weekly session.
Tibial Spine (Eminence) Fracture: reduction and fixation with bioabsorbable pins — Dott. Daniele Priano, Pediatric Orthopaedics · ortopediaevolutiva.com/en/rehabilitation/tibial-spine-fracture-fixation · Information document: it does not replace an in-person assessment.
Other protocols
Hai dubbi o domande?
Per informazioni o chiarimenti puoi contattarmi via email o consultare la pagina con le sedi e i recapiti.
Email: daniele.priano@ortopediaevolutiva.com