Radial Head & Neck Fractures

Radial Head Fracture


Radial Head Fracture Mason 1Radial head fracture




FOOSH (fall on outstretched hand)

- axial load with a valgus force




1.  Valgus stability

- secondary stabilizer

- 30%

- becomes primary stabilizer if medial collateral ligament deficient


2.  Longitudinal stability

- aided by interosseous membrane


3.  Load transfer

- 60% of load at elbow

- with radial head excision, load is transferred to ulno-humeral joint

- increase risk of OA




Radial head


Concave to articulate with capitellum


Articulating portion of rim

- articulates with lesser sigmoid notch of ulna

- covered with thick cartilage


Non articulating portion of rim

- covered with thin cartilage

- safe zone for screws

- 110 degrees

- between radial styloid and lister's tubercle


Lesser sigmoid notch

- articulation with ulna

- guidance for radial head replacement


Lesser sigmoid notchLesser sigmoid notch 2Lesser sigmoid notch


Blood supply

- poor

- single intra-osseous vessel


Hotchkiss modification of Mason Classification


Mason Classification


Type 1: Undisplaced fracture


Intra-articular displacement < 2mm

- no mechanical limitation to forearm rotation

- if in doubt, inject LA into radiocapitellar joint / soft spot

- ensure no mechanical block to rotation


Radial Head Mason 1Radial Head Fracture Mason 1


Type 2: Displacement > 2mm / Motion mechanically limited / Reconstructable


Radial Head Fracture Mason 2Type 3 RH 2Radial Head Fracture Type 2 CT


Type 3:  Severely comminuted fracture / Non reconstructable


Type 3 radial headRH type 3 CT


Type 4: Radial head fracture with elbow dislocation


Mason Type 4 1Mason Type 4 2


CT scan


Aids surgical planning i.e. fixation v arthroplasty

Identifies associated injuries i.e. coronoid fractures


Type 1 coronoidType 2 coronoid


Complicated Radial Head Fracture


1.  Associated injuries


Kaas et al JSES 2011

- MRI of 42 radial head fractures

- 24/42 (57%) elbows had LCL injury

- 1/42 (2%) had a MCL injury

- 16/42 (38%) had an injury of the capitellum

- 1/42 (2%) had a coronoid fracture

- 2/42 (5%) had loose osteochondral fragments


2.  Elbow Dislocation


Terrible triad: radial head fracture, coronoid fracture, LCL injury


3.  Essex Lopresti


Fracture radial head + Disruption DRUJ / interosseous membrane

- dorsal dislocation of DRUJ



- ORIF / replacement radial head

- supinate DRUJ to reduce +/- TFCC repair +/- K wire


Non operative Management




Mason 1


No block to rotation


Mason 2


Lanzerath et al JSES 2021

- systematic review ORIF v nonoperative treatment for Mason II

- 11 studies and 319 patients

- ORIF: 90% good or excellent results, 7% reoperation, OA 5%

- nonoperative: 95% good or excellent results, OA 12%


Yoon et al CORR 2014

- isolated partial radial head fractures displaced > 2 but < 5 mm

- 30 ORIF versus 30 nonoperative

- ORIF group younger and fragments more displaced

- better outcomes in nonoperative group

- 8 cases of mild HO in operative group, and 2 hardware failures


Operative Management


Indications for surgery


van Riet et al Should Elbow 2020


Mechanical block after hematoma aspiration

Displacement > 5 mm

Comminuted fractures (> 2 parts)




Radial Head Fixation

Radial Head Resection

Radial Head Arthroplasty (RHA)


Chaijenkij et al Musculoskeletal Surg 2021

- meta-analysis

- 210 ORIF v 227 RHA v 152 RHR

- RHA had highest outcome scores and lowest complication rate




Kocher approach

- between anconeus and ECU

- LCL or ulna collateral ligament is at risk

- may make repair or reconstruction of LCL easier


Kaplan interval

- split EDC / interval between EDC and ECRB

- protects LCL

- prevents iatrogenic posterolateral instability


AO Surgery Kocher & Kaplan reference


Vumedi Kocher versus Kaplan


Posterior Interosseous Nerve (PIN)


Gruenberger et al JSES Int 2022

- 45 cadavers with EDC splint

- used lateral epicondyle as landmark

- PIN 70 +/- 10 mm from lateral epicondyle


Tornetta et al CORR 1997

- PIN 40 - 48 mm from radiocapitellar joint


Radial Head Fixation


Radial Head ORIFRadial Head ORIF




Significant fragment displacement





Kocher / Kaplan approach

- dissect muscles off capsule

- divide capsule in line with incision / create anterior and posterior flaps


PIN (Posterior Interosseous Nerve)

- pronate forearm to protect PIN

- no Hohmann retractors anteriorly

- limit distal dissection


Safe zone for implants

- posterolateral portion of cartilage

- yellow and thinner, non articulating

- 90o arc between radial styloid and lister's tubercle



- 2.5 or 3.5 headless compression screws

- 5 mm from joint line as radial head surface concave




PIN injury

Intra-articular screws

Hardware failure

Heterotopic ossification


Non union


RH nonunion

Radial head fragment nonunion




Ring et al JBJS Am 2002

- 56 patients with ORIF radial head

- 30 Mason 2, 26 Mason 3

- 13/14 patients with comminuted Mason 3 with > 3 fragments had poor outcome

- 15/15 patients with simple Mason 2 had good outcomes

- best results with 3 or fewer fragments


Radial Head Resection




Elderly patient

Coronoid intact




Elbow dislocation

LCL / MCL / Interosseous membrane disrupted




Proximal radius migration

DRUJ instability and pain

Valgus instability elbow

Arthritis (deceased SA, increased contact stresses)




Antuna et al JBJS Am 2010

- 26 patients < 40 treated with radial head resection

- minimum 15 year follow up

- 81% no elbow pain

- good or excellent results 92%

- all had xray evidence of arthritic change

- increased valgus / carrying angle in all


Radial Head Arthroplasty (RHA)


Radial Head Replacement LateralRadial Head Replacement AP




Cobalt chrome / pyrocarbon / titanium



- allows various sizes of head diameter / thickness

- various stem sizes

- collars to build up radial neck if required


Press fit


Samra et al Should Elbow 2023

- 16 press fit RHA

- 81% survival at 2 years

- high rates of lucent lines and subcollar osteolysis


Radial Head Replacement Lysis LateralRadial Head Replacement Lysis AP


Loose fit


Loose fit allows stem to rotate in medullary canal


Radial Head Replacement Monoblock

Loose fit RHA






1.  Sigmoid notch of ulna


Lesser sigmoid notch


2.  Gapping lateral ulno-humeral joint line


Frank et al JBJS Am 2009

- cadaveric study

- increased medial ulno-humeral joint line gapping with overlengthening of 6 or 8 mm

- increased lateral ulno-humeral joint line gapping with overlengthening of 2 mm



Increased lateral ulnohumeral joint space


Technique Modular Titanium Radial Head Arthroplasty


AO Surgery Reference Radial head arthroplasty


Evolve Radial Head PDF


Vumedi Evolve Radial Head arthroplasty


Radial head replacementsRadial head fragmentsRadial Head Replacement


Lateral approach to elbow

- open capsule

- divide annular ligaments


Excise radial head fragments

- use fragments to estimate diameter and thickness of radial head

- if in doubt, downsize


Deliver radial neck

- Hohman retractor safe posteriorly

- do not place Hohman retractor anteriorly to protect PIN


Ensure neck cut flat 

- avoids maltracking

- need 60% contact of radial neck with prosthesis


Insert trial broaches into neck

- avoid valgus / causes maltracking

- insert trial head diameter and neck length


Check xray to ensure not overstuffed

- lesser sigmoid notch of ulna

- symmetry of ulnohumeral joint


Range elbow


Insert head and neck as one piece


Careful closure of annular ligament


Repair LCL as needed with suture anchors in centre of lateral capitellum




Heijink et al JBJS Rev 2016

- systematic review of radial head arthroplasty

- 30 articles with 727 patients

- 8% revision rate

- Mayo Elbow Performance Score: 85% good or excellent


Davey et al JSES 2021

- systematic review of minimum 8 year outcomes of RHA

- 10 studies with 432 elbows

- 86% minimal or no pain

- 9% loosening

- 27% degenerative change

- 3% RHA revision rate

- 15% removal of implants


Mirzayan et al JSES 2023

- 450 cases

- revision rate 18% for terrible triad versus 10% isolated cases

- increasing radial head diameter associated with increasing revision rate






Over lengthening / over stuffing

Heterotopic ossification


Ulnohumeral joint space

Heterotopic ossification







Radiocapitellar OA


Radial Head Poorly Positioned

Radial arthroplasty malposition




Coronoid / LCL / MCL injuries


Radial neck fracture


Radial Neck FractureRadial Neck Fracture ORIF Screws APRadial Neck Fracture ORIF Screws Lateral


Indications for surgery


> 30o angulated





Incision annular ligament

Elevate supinator with arm pronated


Surgical Options


Headless Compression Screws

Low profile T plate

Intramedullary wire

Radial head replacement


Headless compression screws


Proximal to distal

Cross fracture site


RH 1RH 2



RH 3RH 4RH 5


RH 6RH 7


T plate in safe zone


Radial neck Radial neck orif 1Radial neck ORIF 2




Distal limit is bicipital tuberosity

- pre-contoured low profile plates

- may need to lag articular surface first

- check ROM intra-operatively

- plates often bulky and may limit ROM