Database studies and case series suggest most ulnar fractures associated with distal radius fracture do not benefit from specific treatment. In particular, there is no advantage to fixation of the ulna if it lines up reasonably after the radius fracture is satisfactorily aligned and stabilized.
In the absence of data, and in our opinion, fractures of the ulnar styloid base, head, neck, or shaft of the ulna that remain widely displaced after the radius is reduced and secured likely benefit from reduction and fixation.
Primary distal ulna resection in elderly patients with distal radius fractures concomitant with distal ulna fractures is an acceptable treatment with less complications and reoperations compared to distal ulna fixation.
Case 1: A 45-year-old man fell from a height and fractured his distal radius and the ulnar styloid base (USB) ( Fig. 1 A and B ).
Case 2: A 55-year-old right hand dominant woman fell off her bike resulting in a distal radius fracture on the right side with a concomitant dislocated USB fracture. CT-scan showed a simple articular distal radius fracture (AO type 23C1.3) ( Fig. 2 A–C ).
Open reduction and internal radial fixation was opted for in both cases. However, for which case would additional reduction and internal fixation of the fractured distal ulna be indicated?
Importance of the Problem
Displaced fractures of the distal radius (DRF) can be expected to have rupture of the linkage between the radius and the ulna, caused by either avulsion of the origin of the radioulnar ligaments from the base of the ulnar styloid, or fracture of ulnar styloid base. Of all distal ulnar fractures, 77% are associated with radial fractures.
Fracture of the ulnar styloid base disrupts the origin of the radioulnar ligaments which remains attached to the fragment. In the absence of fracture, similarly displaced fractures likely result in avulsion of the origin from the base without fracture.
Surgeons express concern about distal radioulnar joint (DRUJ) “instability” after fracture of the distal radius. In our opinion, pain in the ulnar side of the wrist pain after fracture of the distal radius is often diagnosed as “instability” for unclear and imprecise reasons. However, the term “instability” is vague and nonspecific because: (1) There is no consensus definition and (2) no reliable and accurate measurement. Palpable and reproducible subluxation and dislocation of the DRUJ with forearm rotation are uncommon in the absence of malalignment of the radius. There is both rotational and translational motion at the DRUJ with pronation and supination. Moreover, evidence shows radiographic nonunion and malalignment of a fracture of the base of the ulnar styloid does not correspond with pain intensity. This results in the risk of misinterpreting alignment on computed tomography as pathological, particularly at relative extremes of pronation and supination.
Fractures of the head or metaphysis of the distal ulna often line up and heal without specific intervention when the distal radius is aligned and secured. Open reduction and internal fixation of the ulna is considered when head, neck, and diaphyseal fractures remain notably malaligned after radius fixation. The degree of displacement that might affect symptoms and limitations is still a matter of debate and needs more evidence.
Fixation of fractures of the ulnar styloid and distal ulna is not straightforward, because of the need to avoid articular surfaces and tendons and because the bone is small and often osteoporotic. A variety of techniques are used. For ulnar styloid fixation frequently used techniques are (1) open reduction and internal fixation (ORIF) using tension band wiring; (2) plate and screw fixation; (3) screw fixation (either headless or headed); and K-wire fixation, sometimes percutaneous. For the ulnar head or metaphyseal fractures fixation is usually accomplished with a plate and screws. Loss of fixation, restriction of DRUJ motion, and iatrogenic injury of the dorsal branch of the ulnar nerve are potential harms of fixation.
Previous database studies and case series addressing fixation of distal ulnar fractures concomitant with distal radius fractures are heterogeneous in fixation techniques, and Level-1 studies are lacking.
Is there a benefit repairing a distal ulnar fracture accompanying an operatively treated unstable distal radius fracture?
In patients with a displaced distal radius fracture with an accompanying distal ulnar fracture, the level of the ulnar fracture and in case of styloid base fractures intraoperative stability tests after distal radius fixation will guide you to ulnar fixation or nonoperative treatment. Ulnar styloid tip fractures are not fixed. Fixation of a displaced ulnar styloid base fracture might be considered if the distal ulna dislocates during forearm rotation after the radial fracture is fixed in a near anatomical position. If the ulnar styloid base fracture is near its usual position, with an expected degree of distal radioulnar laxity and good alignment of the radius, there’s no apparent benefit to fixing the ulnar styloid fracture.
Finding the Evidence
To evaluate available data, a review of literature was performed. The search strategy for embase.com is provided. All other search strategies were adapted from this.
Embase.com : (‘distal ulna’/exp OR (distal-ulna* OR ulna-distal* OR distal-radial-ulnar* OR ((ulna* OR process*) NEAR/1 (styloid* OR stiloid*)) OR ((ulna*) NEAR/3 (head* OR caput* OR subcapit* OR sub-capit*))):ab,ti,kw) AND (‘distal radius fracture’/exp OR (Barton-fracture* OR Colles-fracture* OR Galeazzi-fracture* OR Smith-fracture* OR ((distal*) NEAR/3 (radi*) NEAR/3 (fracture*))):ab,ti,kw)
Articles that were not in the English or German language were excluded.
Quality of the Evidence
There were no randomized controlled trials addressing fixation of distal ulna fractures associated with fracture of the distal radius. Head and neck ulnar fractures and ulnar styloid fractures are evaluated separately.
Level II: 1
Level III: 3
Level II: 1
Level III: 1
Level IV: 3
Level III: 1
Level IV: 2
Ulnar Styloid Base Fractures
One study was designed to prospectively compare fixation with no fixation of ulnar styloid fractures prospectively randomized based on timepoint. When not repairing the ulnar styloid base fracture, they found better grip strength up to 12 weeks in the early postoperative period and regarding range of motion up to three weeks for dorsal flexion and supination, up to 2 weeks for pronation and in the third and fourth week for extension.
Four of 5 cohort studies with a total of 735 patients (range 134–319 patients per study) found no difference in outcomes when a displaced fracture of the distal radius treated with volar locked plating has an associated base of ulnar styloid fracture treated nonoperative or no ulnar styloid fracture. Three studies tested motion, two studies examined pain, all studies reported on PROMs (e.g., DASH, MHQ), and two studies administered physician-based scales (e.g., Gartland and Werley or Mayo).
Nonstyloid Distal Ulna Fractures
One study was designed to prospectively compare fixation with no fixation of ulnar neck fractures prospectively randomized based on timepoint. They found no significant differences between fixed and nonfixed distal ulnar fractures regarding range of motion, grip strength, pain, Gartland and Werley score and radiographic outcomes.
One study retrospectively compared the treatment of ulnar neck fractures to no ulnar fixation. The authors found more complications and more operations in fixed distal ulna fractures.
One study analyzing nonoperative treatment of ulnar head fractures associated with distal radius fractures found that satisfactory results regarding function and pain can be achieved when the distal radius is fixed rigidly. However, radiographic images showed early degenerative arthritis of the DRUJ in not fixed distal ulna fractures.
As for fixation strategies, two cohort studies with a total of 49 patients (24 and 25, respectively) achieved alignment, good function and an acceptable amount of secondary surgery when fixing the ulnar neck and head fractures with distal ulnar hook plate fixation and condylar blade plate fixation.
Two cohort studies of patients treated with acute distal ulnar resection for distal ulna fractures in combination with unstable distal radius fractures with a total of 34 patients (11 and 23, respectively) achieved satisfactory outcomes after distal ulnar resection in older patients and was considered to help avoid secondary surgeries and prevent DRUJ arthrosis.
One study compared distal ulnar resection to fixation of distal ulna fractures in elder patients. They found acceptable results in the ulnar resection group, as no significant changes were found in range of motion, grip strength, pain, patient reported outcomes and radiographic outcomes in comparison to fixed distal ulna fractures. Moreover, the ulnar resection group showed less complications (7 vs 2, P = 0.03) and reoperations (6 vs 1, no P -value given) in comparison to fixed distal ulna fractures.
On average fixation of a fracture of the distal ulna associated with fracture of the distal radius does not improve motion, strength, pain intensity, or radiographic alignment. However, it should be acknowledged that research is limited to database studies and case series on operatively versus nonoperatively treated ulnar fractures and quality of evidence for included studies were very low. It’s possible that prospective studies of selected fractures felt to be at greater risk of DRUJ problems would support fixation. Future studies might also address fixation options for distal ulna fractures after the radius is aligned and fixed.